Steam and Gas Turbines Pune University MCQs

 This set of Steam and Gas Turbines Multiple Choice Questions & Answers  focuses on “Types”.

1. Non Condensing steam turbine can also be called as _________

a) Extraction steam turbine

b) Back pressure steam turbine

c) Impulse steam turbine

d) None of the mentioned

Answer: b

Explanation: The other name for Non condensing turbines is back pressure turbines.

2. Condensing turbine is used for __________

a) central power generation

b) to reduce outlet temperature

c) to increase efficiency of steam

d) none of the mentioned

Answer: a

Explanation: Reducing outlet temperatures and increasing efficiency of the steam are required for every turbine irrespective of its use. So condensing turbines are used for central power generation.

3. Steam turbine is classified on basis of __________

a) type of blades

b) exhausting condition

c) type of Steam flow

d) all of the mentioned

Answer: d

Explanation: Steam turbines are classified by

type of blades, exhausting condition, type of steam flow, division of steam flow, type of compounding.

4. High pressure turbine is a Non-Condensing turbine due to __________

a) exhaust conditions

b) axial flow of the steam

c) pressure-velocity compounding

d) velocity compounding

Answer: a

Explanation: For high pressure turbines exhaust conditions are controlled by regulating valve which makes them to come under the category of Non-Condensing turbines.

5. Impulse blades are in the shape of __________

a) Rain drop

b) Circular

c) Half moon

d) None of the mentioned

Answer: c

Explanation: Blades used in impulse turbines are half moon shaped because as steam enters the moving blade it pushes the blade forward.

6. Astern turbines are used in _________

a) power generation

b) marine purposes

c) aircraft

d) none of the mentioned

Answer: b

Explanation: Astern turbines are those classified based on exhaust conditions and are used for marine purposes.

7. In condensing turbines vacuum is obtained by ____________

a) sudden pressure drop

b) removal of non condensable gases

c) sudden drop in pressure and by removal of non condensable gases

d) none of the mentioned

Answer: c

Explanation: Due to sudden drop in pressure vacuum appears and the remaining non condensable gases are removed from the steam in order to maintain the vacuum.

8. Cross compound steam turbines are once used in _____________

a) generation of electricity

b) marine ships

c) automobiles

d) none of the mentioned

Answer: b

Explanation: Cross compound turbines are once used in marine ships before two stroke diesel engines.

9. When steam reaches turbine blades the type of force responsible for moving turbine blades are _____________

a) Axial force

b) Shear force

c) Longitudinal force

d) None of the mentioned

Answer: a

Explanation: Axial force pushes the turbine blade forward and causes movement in turbine blade.

10. Reaction turbine works with the force obtained from change in pressure energy.

a) True

b) False

Answer: a

Explanation: Reaction turbine runs with the force obtained from change in pressure energy.

This set of Steam and Gas Turbines Multiple Choice Questions & Answers  focuses on “Classification based on Flow Passages and Arrangement”.

1. Multi spool gas turbines are operated at high pressure and high idle rpm.

a) True

b) False

Answer: a

Explanation: Multi spool gas turbine has high pressure spool operating at high idle rpm.

2. Based on type of flow arrangements gas turbines are classified into _____________

a) None of the mentioned

b) Impulse-reaction gas turbine

c) Open cycle gas turbine

d) Axial flow gas turbine

Answer: d

Explanation: Based on the type of flow, Gas turbines are divided into two types. They are axial flow gas turbines, radial flow gas turbines.

3. Identify the types of Gas turbines ___________

a) Turbo jet

b) Turboprop

c) Turbo fan

d) All of the mentioned

Answer: d

Explanation: Gas turbines are further classified into Turbojet, Turboprop, Turbofan, After burning Turbo jet.

4. Gas Turbine Engines, when compared to Reciprocating engines have ________

a) high power to weight ratio

b) low power to weight ratio

c) produce low power

d) none of the mentioned

Answer: a

Explanation: High power to weight ratio is the basic reason behind using Gas turbines in Air crafts thereby replacing reciprocating engines.

5. For producing Same power ____________

a) reciprocating engines will be smaller when compared to Gas turbine engines

b) gas turbine engines are smaller when compared to reciprocating engine counter parts

c) reciprocating engines are complex

d) none of the mentioned

Answer: b

Explanation: As for gas turbine Engine power to weight ratio is less when compared to reciprocating engine.

6. Most preferable Gas turbines are required to be used in _____________

a) fluctuating loads

b) constant loads

c) idling conditions

d) none of the mentioned

Answer: b

Explanation: Gas turbines are preferred to be used in constant load conditions as Fluctuating loads require fluctuating power for which fuel is more consumed.

7. Gas turbines work on ________

a) Otto cycle

b) Dual cycle

c) Brayton cycle

d) Diesel cycle

Answer: c

Explanation: Gas turbines works on brayton cycle.

8. Amount of fuel energy used by compressor is __________

a) half the total energy

b) two third of the total energy

c) one third of the total energy

d) none of the mentioned

Answer: b

Explanation: Two thirds of the total energy produced from combustion of fuel is used by compressor.

9. Gas turbine performance majorly depends on __________

a) compressor efficiency

b) calorific value of fuel used

c) nozzle efficiency

d) none of the mentioned

Answer: a

Explanation: As two thirds of the total energy produced from combustion is used by compressor, compressor efficiency plays a major role in determining Gas turbine performance.

10. Some of the types of combustors available are ___________

a) annular

b) can Annular

c) silo

d) all of the mentioned

Answer: d

Explanation: Types of Combustor are

Annular

Can Annular

Silo.

This set of Steam and Gas Turbines Multiple Choice Questions & Answers  focuses on “Types, Engine and Component – 1”.

1. Pankaj watches a jet in air with a long trail of exhaust gas at its rear. What type of engine do they run on?

a) Prop Jet

b) Back Pressure Gas Turbine

c) Jet Propulsion Gas Turbine

d) Steam turbine

Answer: d

Explanation: Jet propulsion turbine provides high velocity and comfortable flight at very high altitudes.

2. Arrange the words to make a meaningful order: diffuser/exhaust cone/combustor/low pressure compressor/turbine/intercooler/high pressure compressor.

a) low pressure compressor/ turbine/ intercooler/ diffuser/ combustor/ high pressure compressor/ exhaust cone

b) diffuser/ low pressure compressor/ intercooler/ high pressure compressor/ combustor/ turbine/ exhaust cone

c) diffuser/ high pressure compressor/ intercooler/ low pressure compressor/ combustor/ turbine/ exhaust cone

d) combustor/ low pressure compressor/ turbine/ intercooler/ exhaust cone/ high pressure compressor/ diffuser

Answer: c

Explanation: Sequence of components in a Gas Turbine power plant.

3. Oil refineries seek significant application of gas turbine in which form?

a) They utilize waste hot gas from Houdry Cracking Process in order to drive a compressor

b) For peak load application

c) For standby application

d) For locomotive application

Answer: a

Explanation: The waste gas from the process have enough energy to operate a gas turbine which is used to drive a compressor supplying compressed air for the houdry process.

4. Indian Railways has 2000 HP coal burning units with their efficiency as 20%. Calorific value of coal is 30,000 KJ/Kg. Find mass of coal required per hp-sec?

a) 0.2486kg/s

b) 0.1110kg/s

c) 0.3568kg/s

d) 0.2254kg/s

Answer: a

Explanation: Efficiency = work/heat supplied. Work is 2000 hp and heat supplied is mass flow rate * calorific value.

5. Engineers design a Gas Turbine Power Plant. Since the plant initial cost is too high, therefore engineers think to remove the regenerator from their original design. Then, the immediate consequence of the same would be?

a) Compressor work will increase

b) Combustor will require more fuel

c) Turbine will produce more work output per unit of fuel

d) Requirement of Intercooler to compensate for its loss

Answer: b

Explanation: Regenerators act as heat exchangers that heat the air before it enters the combustion chambers through exhaust gas emitting from exhaust cone.

6. Near a natural gas deposits, we require to set up a gas turbine plant. Geologist inform engineers that helium gas is found in abundance here. Hence, engineers seek to use helium as working medium for the gas power plant. This turbine is a _________

a) Multi-shaft open cycle gas turbine

b) Single shaft open cycle gas turbine

c) Closed cycle gas turbine

d) Simple Open cycle Gas Turbine

Answer: c

Explanation: Since the working fluid is other than air, therefore the plant is closed cycle gas turbine.

7. In order to generate energy in Sahara Desert where water is available in significantly low amount. Which system can we employ in such a place?

a) Steam Turbine

b) Gas Turbine

c) Steam Engine

d) Tidal Engine

Answer: b

Explanation: As gas turbine require very little or no water at all for their functioning.

8. Fresh air at 14.7psi enters a compressor of a gas turbine and is compressed isentropically. The gas at the mouth of turbine is at 60 psi pressure and with a specific volume as 50 m 3 /kg. What would be the specific volume of fresh air?

a) 136.54m 3 /kg

b) 125.64m 3 /kg

c) 126.54m 3 /kg

d) 135.64m 3 /kg

Answer: a

Explanation: PV k =constant for isentropic process.

9. Assertion: Twin shaft arrangement of gas turbine must consist of two shafts whether in series or parallel.

Reason: In multi shaft arrangement two or more turbine-compressor combinations are carried on independent shafts. Select the most appropriate options following.

a) Both assertion and reason are correct and reason precisely explains the assertion

b) Both assertion and reason are correct but reason doesn’t exactly explains the assertion

c) Assertion is correct whilst reason is incorrect

d) Assertion is incorrect whilst reason is correct

Answer: d

Explanation: Single shaft arrangement must have all compressors and turbines to be coupled in a series arrangement.

10. The presence of high temperature conditions often limit the use of materials in the plant. Can you predict which of the options would be most suitable material for the gas turbine components?

a) Mn-Ni Alloy

b) Ti-Al-Sn-Zr Alloy

c) Stainless steel

d) Cast Iron

Answer: b

Explanation: Titanium has best high temperature resistance and is almost unreactive even at elevated temperatures.

This set of Steam and Gas Turbines Multiple Choice Questions & Answers  focuses on “Types, Engine and Component – 2”.

1. How many burners are placed in can-annular combustors in gas turbines?

a) 1

b) 3

c) 5

d) Not specific one or more

Answer: d

Explanation: Multiple or single burners are evenly spaced in the combustor.

2. Silo combustors are mounted Internal to gas turbine body.

a) True

b) False

Answer: b

Explanation: Silo combustors are mounted external to the gas turbines.

3. Axial flow turbines are used in ________

a) industrial gas turbines

b) air crafts

c) hybrid vehicles

d) none of the mentioned

Answer: a

Explanation: Axial flow gas turbines are mostly used for industrial purposes.

4. What completes a stage in Turbine expansion?

a) One cycle passing through compressor

b) Row of moving blades followed by a row of stationary blades

c) Stationary blades row followed by Moving blades row

d) None of the mentioned

Answer: c

Explanation: Turbine expansion takes place in stages. One stage comprises of a Row of stationary blades followed by a row of moving blades.

5. What does TRIT in a gas turbine stand for?

a) Turbine Rotor Inlet Temperature

b) Total Raise at Inlet Temperature

c) Temperature Raise In Turbine

d) None of the mentioned

Answer: a

Explanation: TRIT stands for Turbine Rotor Inlet Temperature and TIT stands for Turbine Inlet Temperature.

6. When at idle conditions Gas Turbine Engines use more fuel when compared to Reciprocating engines.

a) True

b) False

Answer: a

Explanation: Though the conditions may be idle but to run the turbine compressor to work, compressor takes as much as the two thirds of the total power produced from combustion and remaining one third is used for power output. So during Idle conditions power output may not be required but compressor uses its 2/3 of energy, whereas reciprocating engines doesn’t require any compressors equipped separately and hence less fuel will be burnt during idle time when compared to Gas turbines.

7. In Gas Turbines Compressors raise the pressure of air by _______ times.

a) 25

b) 15

c) 30

d) 10

Answer: c

Explanation: Compressor work is to raise the pressure of the air at constant volume. In gas turbines, it raises by a factor of 30.

8. In Gas Turbines, Turbine is used to convert _________

a) Kinetic energy to Rotational energy

b) Potential energy of the gases to Rotational energy

c) Heat energy of the gases to Rotational energy

d) None of the mentioned

Answer: a

Explanation: Highly pressurized gas from compressor burns the fuel injected into combustor and those hot gases released move with high velocity towards turbine which rotates the turbine.

9. Hallow perforated piece of heavy metal inside the combustor is called as _________

a) Fuel injector

b) Frame holder

c) Burner

d) None of the mentioned

Answer: b

Explanation: As gas with high pressure enters the combustor with high velocities, for continuous combustion, the combustor in such situations require the frame to be held and therefore frame holder is used.

10. Turbine and Output shaft rotate freely without any connection to the engine.

a) True

b) False

Answer: a

Explanation: Turbine and output shaft are completely stand alone in gas turbine.

This set of Steam and Gas Turbines Multiple Choice Questions & Answers  focuses on “Classification based on Application, Cycle – 1”.

1. Turbojet is a combination of gas turbine with a propeller engine.

a) True

b) False

Answer: a

Explanation: Turbojet is an air breathing jet engine which was used in aeroplane. Both gas turbine and propeller together is a turbojet.

2. A compressor in the gas turbine is driven by the Turbine.

a) True

b) False

Answer: a

Explanation: In a gas turbine both the turbine and compressor are connected to each other where turbine itself drives the compressor eventually.

3. What is bypass ratio in Turbofan?

a) None of the mentioned

b) /

c) /

d) /

Answer: d

Explanation: The term bypass ratio is used in turbofan.In turbofan some of the air enters the engine bypass and rotates the fan while the remaining air rotates the turbine where these two fan and turbine provides the drag force required.Bypass ratio is the ratio of air bypassing the engine to the ratio of air passing through the engine.

4. Turbojet emits ______ engine noise when compared to Turbofan.

a) more

b) less

c) equal

d) none

Answer: a

Explanation: Engine’s noise is directly proportional to the air coming from the engine exhaust.In turbojet more air comes from the engine exhaust which is the reason for more noise.

5. Turboprop engines are used in ________ aircrafts.

a) medium

b) large

c) small

d) none

Answer: c

Explanation: As the air leaving the engine in turboprop is not sufficient to produce required thrust, turboprop engines are used in conditions where less rpms are required.

6. In turboprop engines ____ torque ____ rpm produced from the engine is converted into high rpm low torque.

a) high, low

b) low, high

c) high, high

d) none

Answer: b

Explanation: Turboprop engines generally have low torque and high rpms. In such conditions, a reduction gear is used to convert it into low rpm and high torque so that sufficient drag force can be provided.

7. When turboprop and turbofan operate at same speeds, turboprop consumes ________ fuel.

a) more

b) less

c) equal

d) none

Answer: a

Explanation: Turbofan produces high rpm, low torque but reduction gear is used to convert it into less rpm and high torque to provide required drag force, but turbo fan operates at high rpms, So for turboprop to operate at same speed as of turbofan they require more fuel when compared to turbofan.

8. In turboprop exhaust fan produces ___________

a) more than 25% of the total thrust

b) more than 40% of the total thrust

c) less than 25% of the total thrust

d) less than 10% of the total thrust

Answer: d

Explanation: Due to additional expansion in the turbine system, Energy in the thrust jet is lesser than 10% of the total energy produced by turboprop.

9. Turboprops are not generally operated in high speeds because of ________

a) while speed of the engine increases it looses it efficiency

b) turboprops are not able to produce high speeds

c) turboprops produce high torques

d) none of the mentioned

Answer: a

Explanation: Turboprops cannot be operated at high speeds. Turboprops are operated in between 0.6 and 0.7. When they are operated more than the mentioned speeds they loose their efficiency.

10. A closed cycle gas turbine follows ________

a) Dual Cycle

b) Brayton Cycle

c) Stirling cycle

d) Carnot cycle

Answer: b

Explanation: Closed cycle Gas turbines follow the Brayton cycle.

This set of tricky Steam and Gas Turbines questions and answers focuses on “Classification based on Application, Cycle and Fuel – 2”.

1. This turbine receives steam at high pressure of 600 to 900 psi and discharges it at pressure suitable for supplying to existing low pressure plant. Identify the turbine?

a) Topping Turbine

b) Back-Pressure Turbine

c) Condensing Turbine

d) Extraction Turbine

Answer: a

Explanation: Topping turbine are specially designed turbine for this application in industry.

2. Arjun underwent industrial training in his 2nd year at National Thermal Power Plant. But he was surprised to know that a special turbine is used to meet the electrical energy requirement in the plant itself. Can you identify which turbine did he observe?

a) High Pressure Condensing Turbine

b) House Turbine

c) Gas Turbine

d) Mixed Pressure Turbine

Answer: b

Explanation: Exhaust or extraction steam may be used for feedwater heater.

3. Tanuj and Shyam have a strong discussion over the advantages of Induction-Extraction turbine.

Tanuj: They are employed when a particular manufacturing process require a large quantity of steam at a particular pressure.

Shyam: They are employed when an abundance of waste steam is available at the same pressure. Which one the two you think is correct?

a) Tanuj

b) Shyam

c) Tanuj & Shyam

d) None of the mentioned

Answer: c

Explanation: They are used in both situations.

4. Where in industries do we find back-pressure turbines?

a) At a point in industry where waste steam has to be employed

b) When pressure needs to be applied at rear end

c) When one turbine bolster other

d) There is a requirement of process steam at single pressure

Answer: d

Explanation: These discharge steam into a pressurized piping system to be used for process heating.

5. This turbine is an ingenious method for accomplishing multi velocity staging in a single wheel. Name this turbine?

a) Tangential Turbine

b) Single Stage Impulse Turbine

c) Multi Stage Impulse Turbine

d) None of the mentioned

Answer: a

Explanation: They have reversing chamber equipped with stationary blades which reverses the direction of the steam leaving the moving blades.

6. A marine officer asks you to design a turbine for marine propulsion. Which of the below would be your best choice?

a) Mixed pressure turbine

b) Condensing high pressure regenerative turbine

c) Gas Turbine

d) Tandem-Compound double flow turbine

Answer: b

Explanation: Due to high pressure generated by them.

7. A multipass turbine is a prime mover.

a) True

b) False

Answer: a

Explanation: Prime mover includes every engine that can convert the chemical energy of fuel into useful work.

8. In Europe special types of turbines are used that do not have fixed blades so that pressure drop are necessary in all blade passages. Which turbine is it?

a) Tangential Turbine

b) Axial Flow Turbine

c) Radial Turbine

d) None of the mentioned above

Answer: c

Explanation: They have blades rotating in the opposite direction with two concentric shafts and two generators.

9. You own an industry in which the boiler generates a lot of waste steam which you think could be utilized. Which turbine will you utilize?

a) Mixed Pressure Turbine

b) Back Pressure Turbine

c) Twin-Shaft Gas Turbine

d) Induction-Extraction Turbine

Answer: d

Explanation: They have the capability to admit steam at a given pressure when available.

10. Mac doubts that why do we use House Turbine in National Thermal Power Plants. Can you clear his doubts?

a) The exhaust steam or extraction steam is used for feedwater heating or to supply steam for small turbines serving as auxiliary drives

b) Have huge capacity sufficient enough to run the plant

c) Have minimum losses

d) They can be vertical compounded

Answer: a

Explanation: Their ability to heat feedwater using extraction or exhaust steam.

This set of Steam and Gas Turbines Multiple Choice Questions & Answers  focuses on “Combined Power Plant”.

1. Gas and Steam turbine combined power plant produces more electricity than traditional power plants by how much percent?

a) 25

b) 40

c) 50

d) The given statement was false

Answer: c

Explanation: When steam and gas turbines are jointly used in power plants and the power produced by gas and steam turbines is used in producing electricity.

2. Marine compound power plants are also the combined gas and steam power plants.

a) True

b) False

Answer: a

Explanation: Combined gas and steam power plants is the name given to marine power plants.

3. Maximum supplementary firing means _________

a) minimum fuel that can be fired

b) maximum fuel that can fired with the oxygen available in turbine

c) maximum fuel that can be fired in given time

d) none of the mentioned

Answer: b

Explanation: Maximum supplementary firing means maximum fuel that can be fired with the oxygen available.

4. Due to the limits, upper efficiency of steam turbines is fixed to _________

a) 10-15%

b) 25-45%

c) 20-40%

d) 35-45%

Answer: d

Explanation: In steam and gas turbine combined power plants, steam turbines water is used as working medium. High pressure and high temperatures are required for these high pressures which in turn requires high strengths so expensive alloys like nickel and cobalt are used. These limit the upper efficiency to 35-45%.

5. How many sections does waste heat recovery boiler have in steam generators?

a) 1

b) 2

c) 3

d) 4

Answer: c

Explanation: In steam generators waste heat recovery boilers have 3 sections. They are

Economiser

Evaporator

Superheater.

6. Turbines that are run by exhaust gases are called _______

a) power recovery turbines

b) stepped turbines

c) turbo compounded engine

d) none of the mentioned

Answer: a

Explanation: Turbines that are run by exhaust gases are called power recovery turbines.

7. Combination of two or more thermodynamic processes gives _________

a) decrease in efficiency

b) increase in efficiency

c) increases the temperature at exhaust

d) none of the mentioned

Answer: b

Explanation: When two or more thermodynamic cycles work together their overall combined efficiency increases by 50-60%.

8. By using combined cycle steam and gas power plant _________

a) specific fuel consumption can be decreased

b) efficiency increased

c) specific fuel consumption can be decreased and efficiency increased

d) none of the mentioned

Answer: c

Explanation: If specific fuel consumption is decreased it indirectly increases efficiency.

9. What are turbo-compound engines?

a) Turbines run at exhausts of Otto and diesel cycles

b) Combination of turbofan and turbojet engines

c) Combination of turboprop and turbofan engines

d) None of the mentioned

Answer: a

Explanation: Turbo compound engines are used in air-crafts where turbines run at exhausts of Otto and diesel cycles.

This set of Steam and Gas Turbines Multiple Choice Questions & Answers  focuses on “Advantages”.

1. High power density is the advantage obtained from _______

a) solar Gas turbines

b) steam Turbines

c) cryogenic Gas turbines

d) none of the mentioned

Answer: a

Explanation: Gas turbines have higher power density than steam turbines and in the case of cryogenic gas turbines those could not be operated on solar power.

2. High power to weight ratio is the advantage of _______

a) Turboprop

b) Turbofan

c) Turbojet

d) All of the mentioned

Answer: d

Explanation: All the turboprop, Turbofan, Turbojet have high power to weight ratio when compared to internal combustion engines. That is the reason behind using those gas turbines in place of internal combustion engines in aircrafts.

3. Gas turbine powered engines are smaller than reciprocating engines.

a) True

b) False

Answer: a

Explanation: In gas turbines high power to weight ratio is obtained when compared to reciprocating engines which indicates that for producing equal power in both gas turbine engine and reciprocating engine weight of gas turbine engine should be less which indicates that gas turbine engines are smaller when compared to reciprocating engine.

4. Gas turbine engines moves only in _______ direction.

a) multi

b) two

c) one

d) none

Answer: c

Explanation: In gas turbines turbine rotates due to combusted gases. Combusted gases flow only in one direction, so gas turbine engine moves in one direction only.

5. Gas turbine engines have ______ vibrations when compared to reciprocating engines.

a) less

b) more

c) equal

d) none

Answer: a

Explanation: Gas turbine engines have less rotating parts when compared to reciprocating engines and so gas turbine engines have less vibrations when compared to reciprocating engines.

6. Gas turbine engines have low operating pressures when compared to reciprocating engines.

a) True

b) False

Answer: a

Explanation: In gas turbine engines hot gases from combustors rotate the turbine which means there is separate combustor available in gas turbines where combustion takes place and high temperatures are obtained but turbine does not have high pressure but in the case of reciprocating engines combustion chamber and piston is in the same cylinder, so high pressure is obtained.

7. High operating speeds are obtained in _______

a) Reciprocating turbines

b) Gas turbines

c) Stirling engine

d) None of the mentioned

Answer: b

Explanation: In gas turbines high rpm and low torques are obtained.

8. Consumption of lubricating oil is _______ in gas turbines.

a) low

b) high

c) medium

d) none

Answer: a

Explanation: In reciprocating engines pistons are used but not in the case of gas turbines. Hence low lubrication oil is required.

9. At idle conditions gas turbine engines are ________ efficient than reciprocating engines.

a) more

b) less

c) moderately

d) none

Answer: b

Explanation: In gas turbines two thirds of total energy produced is used in by compressor where as reciprocating engines have no compressor. So gas turbines use more power than reciprocating engines at idle conditions.

10. Reciprocating engines require __________ startups than Gas turbines.

a) longer

b) moderate

c) shorter

d) none

Answer: c

Explanation: Initially for reciprocating engines to start only combustion process need to be started but in the case of Gas turbines both compressor and combustor need to start. So Gas turbines take longer startups when compared to reciprocating engines.

This set of Steam and Gas Turbines Multiple Choice Questions & Answers  focuses on “Introduction”.

1. Gas turbines burn fuel to run their turbines.

a) True

b) False

Answer: a

Explanation: Gas turbines have combustors where fuels are burned and the exhaust at high pressure is used to run the turbine.

2. Gas turbine is also called as _______________

a) Velocity turbine

b) Steam turbine

c) Combustion turbine

d) None of the mentioned

Answer: c

Explanation: In gas turbines fuel is combusted in combustor and hence it is also called as combustion turbines.

3. In gas turbine upstream compressor is connected to downstream turbine.

a) True

b) False

Answer: a

Explanation: In gas turbines both compressor and turbine are connected by same shaft.

4. Gas turbine is a type of ___________ combustion engine.

a) depends

b) external

c) internal

d) none of the mentioned

Answer: c

Explanation: In gas turbine combustion takes place inside the engine and hence it is also a type of internal combustion engines.

5. _________ gas turbines are called as Auxiliary power units.

a) Smaller

b) Larger

c) Medium

d) None of the mentioned

Answer: a

Explanation: Smaller gas turbines are called as auxiliary power units.

6. Auxiliary power units are used to supply __________ air for air conditioning and ventilation.

a) low pressure

b) high pressure

c) medium pressure

d) none of the mentioned

Answer: b

Explanation: APUs supply compressed air for air conditioning. High pressure air is also called as compressed air.

7. All modern helicopters are powered by _________ engines.

a) Turbo shaft

b) Turbo jet

c) Turbo prop

d) None of the mentioned

Answer: a

Explanation: Turbo shaft engines are used to power trains, helicopters, etc.

8. Micro turbines are used to power _________

a) None of the mentioned

b) Air crafts

c) Ships

d) Hybrid vehicles

Answer: d

Explanation: Micro turbines are used to power hybrid vehicles whereas air crafts are powered by turbofans, turbojets, etc.

9. Micro turbines are also known as ___________

a) Turbo alternators

b) Turbo generators

c) Turbo alternators & generators

d) None of the mentioned

Answer: c

Explanation: Micro turbines are also called as turbo alternators.

10. Micro turbines are also called as ____________

a) Turbo alternators

b) Turbo alternators & generators

c) Turbo generators

d) None of the mentioned

Answer: b

Explanation: Micro turbines are also called as turbo generators.

This set of Steam and Gas Turbines Multiple Choice Questions & Answers  focuses on “Fundamentals of Thermodynamics”.

1. Steam turbines work on __________

a) Otto cycle

b) Dual cycle

c) Rankine cycle

d) None of the mentioned

Answer: c

Explanation: Otto cycle petrol is used as fuel, Rankine cycle is the process followed in steam turbines.

2. Gas turbines work on ___________

a) Rankine cycle

b) Diesel cycle

c) Brayton cycle

d) None of the mentioned

Answer: c

Explanation: Rankine cycle is used in steam turbines. Brayton cycle is followed in gas turbines.

3. Generally, water is used as working fluid in rankine cycle.

a) True

b) False

Answer: a

Explanation: Rankine cycle is followed in steam turbines. In steam turbines generally, water is used as working fluids.

4. Ideal Brayton cycle consists of ________

a) Isoentropic process and Isobaric process

b) Adiabatic process and Isobaric process

c) Adiabatic process

d) None of the mentioned

Answer: a

Explanation: Ideal brayton cycle works on isoentropic process and isobaric process.

5. Actual Brayton cycle works on _________

a) Isoentropic process and Isobaric process

b) Adiabatic process and Isobaric process

c) Isoentropic process

d) None of the mentioned

Answer: b

Explanation: Actual brayton cycle works on Adiabatic process and Isobaric process slight deviations from actual brayton cycle.

6. Brayton cycle is also known as __________

a) Joule cycle

b) Regenerative cycle

c) Carnot cycle

d) None of the mentioned.

Answer: a

Explanation: Regenerative cycle is a closed loop usage of working fluid in rankine cycle. Brayton cycle is also called a joule cycle.

7. Brayton cycle is also called an Ericsson cycle.

a) True

b) False

Answer: a

Explanation: Brayton cycle is also called an ericsson cycle.

8. Brayton cycles are further divided into ______ types.

a) 2

b) 3

c) 4

d) None of the mentioned

Answer: a

Explanation: Brayton cycle is further divided into two types. They are open cycle and closed cycle.

9. Internal combustion chamber is used in _______ Brayton cycle.

a) open

b) closed

c) depends

d) none

Answer: a

Explanation: Internal combustion chambers are present in open cycles to heat the working fluid.

10. Heat exchanger is used in a closed Brayton cycle.

a) True

b) False

Answer: a

Explanation: Heat exchangers are used in closed cycles to raise the temperature of working fluid.

This set of Steam and Gas Turbines Multiple Choice Questions & Answers  focuses on “Carnot, Rankine and Reheat cycle”.

1. Carnot engine follows ____________

a) Isothermal process

b) Isoentropic process

c) Isothermal and Isoentropic process

d) None of the mentioned

Answer: c

Explanation: Carnot cycle process follows 4 process. They are

Isothermal heat addition

Reversible adiabatic expansion

Reversible isothermal compression

Reversible adiabatic heat rejection.

2. Clausius inequality is applied at _____________

a) reversible isothermal heat addition

b) reversible adiabatic expansion

c) reversible isothermal compression

d) reversible isothermal heat rejection

Answer: c

Explanation: In reversible adiabatic compression entropy is same as from reversible isothermal heat addition and this can be found out by clausius inequality.

3. During reversible adiabatic explansion and compression entropy doesnot change.

a) True

b) False

Answer: a

Explanation: Adiabatic process mean there is no heat transfer and if there is no heat transfer entropy doesnot change.

4. What happens if all the process in carnot cycle be reversed?

a) Works as heat engine

b) PMM1 occurs

c) Works as refrigerator

d) PMM2 occurs

Answer: c

Explanation: When all the process in carnot cycle be reversed heat is absorbed from the body and reduces the temperature of the body which means a refrigerator. When carnot cycle is not reversed it acts as a heat engine.

5. Working fluid of rankine cycle usually _____________

a) Water

b) Methane

c) Hard water

d) None of the mentioned

Answer: a

Explanation: Water is used as working fluid in rankine cycle.

6. Steam turbines work on __________

a) Rankine cycle

b) Carnot cycle

c) Dual cycle

d) None of the mentioned

Answer: a

Explanation: Rankine cycle is generally used where heat energy is to be converted in mechanical energy.

7. In non ideal rankine cycle the compression of pump and expansion of turbine is isoentropic.

a) True

b) False

Answer: b

Explanation: In general isoentropic cases are harder to occur and hence in rankine cycle they doesnot exist as isoentropic process.

8. What is the use of reheat cycle in steam turbines?

a) To remove the moisture from the steam

b) To increase the steam temperature

c) To increase steam pressure

d) None of the mentioned

Answer: a

Explanation: Reheat cycle is worked with rankine cycle to remove the moisture from the steam.

9. In rankine cycle with reheat how mny turbines work?

a) 1

b) 2

c) 3

d) 4

Answer: b

Explanation: One turbine is to produce work and the other turbine is to reheat.

10. Reheat temperatures are very close to ______ temperature.

a) inlet

b) outlet

c) intermediate

d) none of the mentioned

Answer: a

Explanation: After passing from the first turbine again the steam enters the boiler to raise their temperature close to the inlet temperature and then enters the low pressure turbine.

This set of Steam and Gas Turbines Multiple Choice Questions & Answers  focuses on ” Carnot, Rankine and Reheat Cycle-2″.

1. The cycle of evaporation and rain in nature can be assumed to be a kind of Carnot cycle. If ocean water instead of evaporation are boiled by the heat of Sun at a constant temperature of 100 deg C and the condensation of steam into water droplets within the clouds occur at constant temperature of -20 deg C. Find the thermal efficiency of Carnot cycle of nature?

a) 0.2777

b) 0.3030

c) 0.3333

d) 0.50

Answer: b

Explanation: Carnot thermal efficiency = 1-/.

2. How is it advantageous to expand steam at 250 deg C in a turbine as compared to expanding saturated steam in similar turbine?

a) Enhances the thermal efficiency of the cycle

b) Reduces the mechanical damage caused to turbine blades due to wet steam

c) Increases the mean temperature of heat addition

d) All of the mentioned

Answer: d

Explanation: Superheating steam makes expansion within turbine to take place in dry region to a greater extent.

3. In a steam turbine power plant, the boiler feedwater temperature is marked as 30 deg C, ocean as sink with temperature 20 deg C and desired thermal efficiency of the plant is 0.46. Find the temperature of steam entering the turbine?

a) 500degC

b) 505.55degC

c) 507.62degC

d) 509.18degC

Answer: d

Explanation: Mean temperature of heat addition = /2.

4. In a newly developed innovative idea brought up by CSIR in India, gas turbine exhaust gas are being utilized to convert feedwater into steam. Certain data of the experiment are as follows: mass flow rate of exhaust gas = 40 kg/hr, enthalpy of exhaust gas at the time of their exit from gas turbine is 600 kJ/kg, steam turbine output as measured by brake dynamometer = 60 hp-sec, thermal efficiency of steam power plant is 0.25, efficiency of exhaust gas in converting feedwater into steam is taken as 50%. Find the enthalpy of exhaust gas remaining after they generate steam from feedwater?

a) 350.0KJ/Kg

b) 241.2KJ/Kg

c) 112.45KJ/Kg

d) 512.56KJ/Kg

Answer: b

Explanation: Heat added = difference of enthalpies * efficiency of exhaust gas in converting feedwater into steam and then apply thermal efficiency formula for Carnot efficiency.

5. Why does Carnot cycle has maximum efficiency?

a) Since all the processes in Carnot cycle are completely reversible

b) Since only process of expansion and compression are reversible

c) Since only the process of heat addition and heat rejection are reversible

d) Since all processes involved are irreversible

Answer: a

Explanation: All the processes in Carnot cycle are completely reversible.

6. A researcher during an experiment found that mean temperature of heat addition and heat rejection for a steam power plant operating on a Carnot cycle is 127 deg C and 27 deg C respectively. Later, he calculated the thermal efficiency of the steam cycle. Can you predict what was it?

a) 0.20

b) 0.25

c) 0.30

d) 0.35

Answer: b

Explanation: Thermal efficiency of a Carnot cycle is given by /.

7. If Carnot cycle has maximum possible thermal efficiency, then why don’t the steam turbine power plants run on Carnot cycle?

a) Because the process of heat addition is at constant temperature

b) As mean temperature of heat addition is quite low in case of Carnot cycle

c) Since work consumed by compressor is approximately equal to work produced by turbine

d) Because boiler can’t be maintained at constant pressure in Carnot cycle

Answer: c

Explanation: As compressor and turbine both work on wet steam, therefore they don’t have significant difference in their work.

8. The mass of coal used in boiler of a steam power plant is 20 ton per hour and calorific value of lignite is 13600 KJ/kg. Also, if the entropy of steam entering turbine is 750 J/K and that of feedwater entering the boiler is 550J/K. Find the mean temperature of heat addition?

a) 100 deg C

b) 115 deg C

c) 110 deg C

d) 105 deg C

Answer: d

Explanation: Tmean = Q/.

9. In a solar operated steam power plant, water is converted into steam via solar heat. If the effective area of solar plate is 200m 2 , value of solar constant is 1.362KW per m 2 , efficiency of solar components is 17% and overall thermal efficiency of steam cycle desired is 12%. Find the turbine power output?

a) 45KW

b) 22.46KW

c) 5.55KW

d) 16.54KW

Answer: c

Explanation: Efficiency of steam cycle = ).

10. A boiler feed pump is used to raise ___________

a) Static pressure of feedwater

b) Dynamic pressure of feedwater

c) Static & Dynamic pressure of feedwater

d) None of the mentioned

Answer: a

Explanation: Since water needs to be brought to boiler pressure and is not in motion.

This set of Steam and Gas Turbines Multiple Choice Questions & Answers  focuses on “Effect of Pressure and Temperature”.

1. When boiler pressure is increased efficiency is ____________

a) decreased

b) increased

c) remains constant

d) none of the mentioned

Answer: b

Explanation: When boiler pressure is increased efficiency is increased.

2. Why is operating pressure of boiler designed?

a) To maintain economic equivalence

b) For not decreasing efficiency

c) No such operating pressures are designed

d) None of the mentioned

Answer: a

Explanation: If boiler pressure is increased efficiency also increases. But if we keep on increasing boiler pressure to increase efficiency, Boilers that work under high pressure as costly and so boiler operating pressures are designed so that for a particular boiler it does not work beyond that pressure and it maintains economical equivalence.

3. When boiler pressure is increased __________

a) efficiency is increased

b) Qh is increased

c) efficiency & Qh is increased

d) none of the mentioned

Answer: c

Explanation: When boiler pressure is increased Qh increases as a result efficiency is increased.

4. Can we keep on increasing the pressure of the boiler to increase its efficiency?

a) Yes

b) No

Answer: b

Explanation: Boilers that work under high pressure are much more costly.

5. What happens to the efficiency when temperature is increased in rankine cycle?

a) Increased

b) Decreased

c) Remains constant

d) None of the mentioned

Answer: a

Explanation: When the temperature is increased reheating capacity of the steam increases and thus efficiency also increases.

6. Increase in temperature increases __________

a) reheating capacity of the fluid

b) thermal efficiency

c) reheating capacity of the fluid & thermal efficiency

d) none of the mentioned

Answer: c

Explanation: When reheating capacity is increased it automatically increases the thermal efficiency.

7. When condenser pressure is lowered efficiency _________

a) increases

b) decreases

c) does not effect

d) none of the mentioned

Answer: a

Explanation: When operating pressure of condenser is lowered, Heat rejecting temperature also lowers which eventually increases the efficiency.

8. Superheating the steam increases efficiency.

a) True

b) False

Answer: a

Explanation: Average Temperature of steam can be increased without increasing the pressure by superheating.

9. Superheating the steam results in __________

a) increasing the efficiency

b) decreases the moisture content

c) increasing efficiency & decreases the moisture content

d) none of the mentioned

Answer: c

Explanation: Superheating the steam increases the steam temperature and also decreases the moisture content in the steam.

10. When boiler pressure is increased __________

a) temperature also increased

b) efficiency also increases

c) temperature & efficiency increases

d) none of the mentioned

Answer: a

Explanation: When boiler pressure is increased steam temperature increases which increases efficiency.

This set of Steam and Gas Turbines Multiple Choice Questions & Answers  focuses on “Efficiencies”.

1. What does thermodynamic efficiency of steam turbine mean?

a) Ratio of power developed to the power that can be developed by ideal turbine

b) Ratio of power that can be developed by ideal turbine to the power developed by the actual turbine

c) Ratio of inlet temperature to outlet temperature

d) None of the mentioned

Answer: a

Explanation: Thermodynamic efficiency is the ratio of power developed by actual turbine to the power that can be developed by ideal turbine.

2. What does aerodynamic efficiency mean?

a) Energy that can be extracted from a given volume of steam at given temperature and pressure

b) Amount of steam turbine blade can allow to flow inside

c) Amount of energy contained in steam

d) None of the mentioned

Answer: a

Explanation: Aerodynamic efficiency means energy that can be extracted from given volume of steam at given pressure and temperature.

3. If efficiency of boiler increases then efficiency of steam turbine ______

a) decreases

b) increases

c) cannot be determined

d) none of the mentioned

Answer: b

Explanation: If the efficiency of steam boiler increases temperature also increases which indirectly increases its efficiency.

4. If condenser efficiency increases then overall efficiency of steam turbine _______

a) decreases

b) increases

c) remains constant

d) none of the mentioned

Answer: b

Explanation: If condenser efficiency increases it raises the steam temperature and hereby increasing overall efficiency.

5. What does combustion efficiency mean?

a) Boiler ability to burn the fuel to fuel that is not burned and amount of air present at exit

b) Calorific value that can be obtained by burning a fuel

c) Energy that is released when fuel is burned

d) None of the mentioned

Answer: a

Explanation: Combustion efficiency is used to denote the amount of fuel burned by using the air.

6. What does fluid to fuel efficiency mean?

a) It indicates the overall efficiency of the boiler

b) Indicates fuel efficiency

c) Overall efficiency excluding boiler efficiency

d) None of the mentioned

Answer: a

Explanation: Fluid to fuel efficiency indicates overall efficiency including Boiler efficiency, conduction, convection and radiation, etc.

7. The total energy in the fuel is called as _____________

a) boiler efficiency

b) boiler energy

c) gross calorific value

d) none of the mentioned

Answer: c

Explanation: Gross calorific value indicates the total energy a fuel can release when burned.

8. Flue gases _______ efficiency.

a) decreases

b) increases

c) does not effect

d) none of the mentioned

Answer: b

Explanation: Flue gases effect combustion of the fuels and due to that it affects the overall efficiency.

9. Nozzle efficiency can be defined by __________

a) ratio of kinetic energy of the steam leaving the nozzle to the potential energy available with the steam while entering

b) pressure of the steam leaving the nozzle to pressure of the steam entering the nozzle

c) temperature of the steam leaving the nozzle to the temperature of the steam entering the nozzle

d) none of the mentioned

Answer: a

Explanation: Nozzle is used to convert the potential energy of the steam available into kinetic energy to run the turbine.

10. What is the typical efficiency of the nozzle?

a) 0.45-0.56

b) 0.9-0.99

c) 0.5-0.7

d) 0.67-0.86

Answer: b

Explanation: The typical efficiency of the nozzle is between 0.9 and 0.99.

This set of Steam and Gas Turbines Multiple Choice Questions & Answers  focuses on “Heat and Steam Rate – 1”.

1. Heat rate is used to define the efficiency of steam power plant.

a) True

b) False

Answer: a

Explanation: Heat rate = /.

2. Inverse of efficiency is called as ____________

a) steam rate

b) heat rate

c) heat utilized

d) none of the mentioned

Answer: b

Explanation: From the formula, we can identify heat rate is the inverse of steam rate.

3. To increase plant efficiency heat rate is to be _________

a) increased

b) decreased

c) no relation with the heat rate

d) none of the mentioned

Answer: b

Explanation: As heat rate is inverse of plant efficiency, to increase plant efficiency heat rate is to be decreased.

4. What are the units of heat rate?

a) Kw/hr

b) No units

c) BTU/KWh

d) None of the mentioned

Answer: c

Explanation: Chemical energy input units are BTU and electrical energy output units are KWh. So units of heat rate are BTU/KWh.

5. Chemical energy of the fuel can be calculated by _________

a) Chemical energy of fuel =  * 

b) Chemical energy of fuel =  * 

c) Cannot be determined theoretically

d) None of the mentioned

Answer: a

Explanation: Chemical energy of fuel =  * .

6. Heat rate losses that can be directly effected by actions of operators is called ______

a) uncontrollable losses

b) controllable losses

c) non-Value added losses

d) none of the mentioned

Answer: b

Explanation: Heat rate losses than be directly effected by actions of operator are called controllable losses.

7. Heat rate deviation can be defined as _______

a) difference between actual and target heat rate

b) difference between heat rates at maximum and minimum temperatures

c) difference between calorific value of ideal fuel and actual fuel used

d) none of the mentioned

Answer: a

Explanation: Heat rate deviation can be defined as the difference between the actual and target heat rates.

8. Steam flow rate can be calculated by _______

a) 3600/p

b) 3600 He/p

c) 3600 P/He

d) None of the mentioned

Answer: c

Explanation: Steam flow rate can be calculated by Ms = 3600 p/He.

9. The rate at which boiler in steam turbine produces steam is called __________

a) Steam rate

b) Steaming rate

c) Heat rate

d) None of the mentioned

Answer: b

Explanation: The rate at which the boiler produces steam is called steaming rate.

10. Heat rate can be used to find annual fuel costs.

a) True

b) False

Answer: a

Explanation: Annual Fuel cost = Heat rate deviation * Fuel capacity * Capacity factor *  * Time.

This set of Steam Turbine Interview Questions and Answers focuses on “Heat and Steam Rate”.

1. Heat rate defines how much energy is to be expanded for obtaining a unit of useful work.

a) True

b) False

Answer: a

Explanation: Heat rate means the amount of energy that must be expanded for obtaining an unit of useful work.

2. What is heat rate in turbine?

a) Heat required for unit of power generated in specific conditions and specific fuel burning

b) Amount of heat required to expand turbine blades

c) Amount of heat required to increase pressure of steam

d) None of the mentioned

Answer: a

Explanation: Heat rate in turbines is defined as heat required to generate unit power in turbine at specific fuel being burned at specific conditions.

3. For calculating heat rate in steam turbines enthalpy is calculated.

a) False

b) True

Answer: b

Explanation: Heat rate can be calculated by using enthalpy method.

4. Steam turbine governing can be defined as __________

a) increasing the steam speed

b) adjusting the governors for particular speeds

c) controlling the flow rate of steam

d) none of the mentioned

Answer: c

Explanation: Governors are used to control the fuel needed to the load and they are no way related to the steam turbine governing. Steam turbine governing is controlling the flow rate of steam.

5. Why is steam turbine governing used?

a) To increase the steam speed

b) To maintain steam speed constant

c) To decrease the steam speed

d) None of the mentioned

Answer: b

Explanation: Flow rate if steam is controlled to maintain the constant speed.

6. In nozzle governing the flow rate is controlled by ____________

a) opening and closing the valves at nozzle

b) adding more number of nozzles

c) increasing nozzle efficiency

d) none of the mentioned

Answer: a

Explanation: Opening and closing of valves at nozzle is called nozzle governing.

7. During overload of turbines __________ are used.

a) throttle governing

b) nozzle valves

c) bypass governing

d) none of the mentioned

Answer: c

Explanation: During overload conditions fresh steam is added into later stages called as bypass governing.

8. When is emergency governing used?

a) Speed of shaft increased above 110%

b) When turbine is shut down due to overload

c) When Low steam is entering

d) None of the mentioned

Answer: a

Explanation: When speed of shaft is increased to 110% then emergency governing is used to control the speed.

9. When balancing of the turbine is disturbed ___________ is used.

a) Potter governor

b) Centrifugal governor

c) Emergency governor

d) None of the mentioned

Answer: c

Explanation: Emergency governor is also used when balancing of the turbine is disturbed.

10. When lubrication is failed _____________ is used.

a) Centrifugal governor

b) Emergency governor

c) Potter governor

d) None of the mentioned

Answer: b

Explanation: Emergency governor is used in all emergency situations like when the lubrication system is failed, when speed is increased when balancing is disturbed etc.

This set of Steam and Gas Turbines Multiple Choice Questions & Answers  focuses on “Sterling and Ideal Ericsson Cycle”.

1. Isoentropic processes in carnot cycle when replaced by constant volume process is called as _______

a) Dual cycle

b) Ericsson cycle

c) Stirling cycle

d) None of the mentioned

Answer: c

Explanation: Isoentropic process in carnot cycle when replaced by constant volume process is called as Stirling process.

2. Stirling cycle is reversible.

a) True

b) False

Answer: a

Explanation: Since isoentropic process in carnot cycle is replaced by constant volume process, Stirling cycle can be reversible.

3. Stirling cycle can also be called a closed regenerative cycle.

a) True

b) False

Answer: a

Explanation: Since Stirling cycle is reversible and is a closed cycle it can also be called as closed regenerative cycle.

4. Stirling cycle can also be categorized as ________

a) internal heat engine

b) external heat engine

c) internal combustion engine

d) none of the mentioned

Answer: b

Explanation: When work is supplied to Stirling engine, heating or cooling can be produced as per requirement, So Stirling cycle is categorized as an external heat engine.

5. Processes in Stirling cycle are _______________

a) Compression, Heat addition, Expansion, Heat removal

b) Compression, Heat addition, Expansion

c) Heat addition, Expansion, Heat removal

d) None of the mentioned

Answer: a

Explanation: Stirling cycle consists of four processes. They are

Compression

Heat addition

Expansion

Heat removal.

6. Compression process that takes place in Stirling engine is _________

a) Constant volume

b) Isothermal

c) Constant pressure

d) None of the mentioned

Answer: b

Explanation: In Stirling engine, Isothermal compression takes place.

7. In Stirling engine, pistons are arranged in __________

a) co-linear position

b) linear position

c) parallel position

d) none of the mentioned

Answer: a

Explanation: In Stirling engines, co-linear pistons are arranged.

8. In Ericsson cycle, heat addition is done by ___________

a) none of the mentioned

b) isochoric heat addition

c) isothermal heat addition

d) isobaric heat addition

Answer: d

Explanation: Heat addition is done by constant pressure process in Ericsson cycle.

9. Ericsson cycle is also known as external combustion engine.

a) True

b) False

Answer: a

Explanation: In Ericsson cycle, combustion is done externally and hence it is called an external combustion engine.

10. Separated flow counter – current heat ex-changer is called as __________

a) aeriator

b) regenerator

c) economiser

d) recuperator

Answer: d

Explanation: Recuperator can be referred as separated flow counter – current heat ex-changer.

This set of Gas Turbine Questions and Answers for freshers focuses on “Ideal, Actual Intercooling and Reheat”.

1. A gas turbine is called as __________

a) Expansion turbine

b) Combustion turbine

c) Compression turbine

d) None of the mentioned

Answer: b

Explanation: In gas turbine energy is provided to rotate the turbine by combusting the fuel and hence it is also called a combustion turbine.

2. A combustion chamber in gas turbine is present in between upstream compressor and down stream turbine.

a) True

b) False

Answer: a

Explanation: Atmospheric air is compressed in compressor and then fuel is sprinkled on compressed air in combustion chamber and fuel is burnt there. The energy produced in combustion chamber is used to rotate the turbine.

3. In ideal gas turbine isoentropic and isobaric process takes place.

a) True

b) False

Answer: a

Explanation: In ideal gas turbine

isoentropic compression

isobaric compression

isoentropic expansion takes place.

4. In actual gas turbine, mechanical energy is converted into heat by _________

a) none of the mentioned

b) frictional losses in compressor

c) no mechanical energy is converted into heat energy

d) friction between piston and cylinder

Answer: d

Explanation: In combustion chamber friction is present in between piston and cylinder and that is why some of the mechanical energy is converted into heat energy.

5. A typical heat exchanger removing heat from compressor is called as intercooler.

a) True

b) False

Answer: a

Explanation: An intercooler is an heat exchanger removing heat from compressor.

6. In IC engines intercooler is used to __________

a) overall efficiency

b) increase volumetric efficiency

c) heat rate

d) none of the mentioned

Answer: b

Explanation: Inter cooler reduces unwanted heat from compressor and can increase volumetric efficiency.

7. Knocking of the fuel can be reduced by _________

a) using intercooler

b) decreasing air intake pressure

c) increasing air intake

d) none of the mentioned

Answer: a

Explanation: By using intercooler air intake is decreased and hence it reduces knocking of fuel.

8. Compression with intercooler causes ________

a) increase in the compressor work

b) decrease in the compressor work

c) increases the overall efficiency

d) none of the mentioned

Answer: b

Explanation: When intercooler is used it uses some of the work produced and reduces the net work done by compressor.

9. Extra cooling can be done by __________

a) decreasing no of fins

b) increasing number of fins

c) spraying mist on inter cooler surface

d) none of the mentioned

Answer: c

Explanation: Extra cooling can be done by spraying mist on the surface of intercooler.

10. Using of intercooler and reheating process ________ efficiency.

a) increases

b) decreases

c) does not change

d) none of the mentioned

Answer: a

Explanation: When intercooler and reheater are used in gas turbines they increase efficiency by reducing the wastage of heat.

This set of Steam and Gas Turbines Multiple Choice Questions & Answers  focuses on “Combined effect of intercooling, reheating and regeneration”.

1. Regenerator is also called as ___________

a) Intercooler

b) Reheater

c) Recuperator

d) None of the mentioned

Answer: c

Explanation: Regenerator is also called as a recuperator.

2. When recuperator is used thermal efficiency is ______

a) decreased

b) increased

c) doesn’t change

d) none of the mentioned

Answer: b

Explanation: When regenerator is used thermal efficiency is increased.

3. Inlet temperature of regenerator is __________

a) same as of the inlet exhausted gases

b) more than the inlet exhausted gases

c) less than the inlet exhaust gases

d) none of the mentioned

Answer: a

Explanation: Inlet temperature of regenerator is same as of inlet exhaust gases.

4. Effectiveness can be defined as _________

a) decrease in exhausted gases

b) inverse of the efficiency

c) ratio of heat rate to the mass entering

d) ratio of Actual heat transferred to the maximum heat transferred

Answer: d

Explanation: Effectiveness is the ratio of actual heat transferred to maximum heat that can be transferred.

5. Generally effectiveness of regenerators are ___________

a) 0.95

b) 0.66

c) 0.77

d) 0.85

Answer: d

Explanation: Generally effectiveness is 0.85 for a regenerator.

6. Compression can be taken place by _____________

a) isoentropic compression

b) isothermal compresion

c) two stage compression process

d) all of the mentioned

Answer: d

Explanation: Compression can be taken place by isoentropic compression or isothermal compression or by two stage compression.

7. Isoentropic compression requires maximum work.

a) True

b) False

Answer: a

Explanation: Isoentropic compression requires maximum work.

8. Isothermal compression requires minimum work.

a) True

b) False

Answer: a

Explanation: Isothermal compression requires minimum work.

9. By two stage compression work output from turbine is _______

a) decreased

b) increased

c) remains constant

d) none

Answer: b

Explanation: Two stage compression increases work output from turbine.

10. When equal pressure ratio are maintained at two stages the work output _______

a) increases

b) decreases

c) optimum

d) none of the mentioned

Answer: a

Explanation: When equal pressure ratio is maintained work output increases.

This set of Gas Turbines question bank focuses on “Closed Cycles and Operating Media Other than Air”.

1. A closed cycle gas turbine uses gas as a working fluid.

a) True

b) False

Answer: a

Explanation: In a closed cycle gas turbine air is used as working fluid and working fluid moves in closed thermodynamic cycle.

2. In a closed cycle gas turbine heat is supplied from ____________

a) internal source

b) external source

c) combustion chamber

d) none of the mentioned

Answer: b

Explanation: In a closed cycle gas turbine heat is supplied from external source.

3. Pebble bed modular is reactor coupled with _________

a) helium closed cycle gas turbine

b) argon closed cycle gas turbine

c) gas cooled reactors

d) none of the mentioned

Answer: a

Explanation: Pebble bed modular reactor was made to work with helium closed cycle gas turbine.

4. At low temperature super critical CO2 closed cycle gas turbine has ________ efficiency when compared to helium closed cycle gas turbine.

a) low

b) high

c) optimum

d) none of the mentioned

Answer: b

Explanation: At low temperatures super critical CO2 closed cycle gas turbine has higher efficiency.

5. At high pressure super critical CO2 closed cycle gas turbine has ____________ efficiency when compared to helium closed cycle gas turbine.

a) optimum

b) high

c) low

d) none of the mentioned

Answer: c

Explanation: At high pressures super critical CO2 closed cycle gas turbine has low efficiency.

6. ML-1 nuclear reactor uses ________________

a) nitrogen based closed cycle gas turbine

b) helium based closed cycle gas turbine

c) super critical CO 2 closed cycle gas turbine

d) none of the mentioned

Answer: a

Explanation: In 1961 ML-1 Nuclear reactor used nitrogen based closed cycle gas turbine.

7. ML-1 Nuclear reactor works under ___________

a) 0.7 MPa

b) 0.9 MPa

c) 0.5 MPa

d) 0.3 MPa

Answer: b

Explanation: Nitrogen based closed cycle gas turbine works under 0.9MPa.

8. In thermodynamic cycles input to working fluid is given using ________

a) compressor

b) condensor

c) recuperator

d) none of the mentioned

Answer: a

Explanation: When it enters compressor its temperature is raised by means of increasing its pressure and that is how energy input is given.

9. Working fluids used in rankine cycles are _______

a) water/Steam

b) pentane

c) toluene

d) all of the mentioned

Answer: d

Explanation: Working fluids used in rankine cycles are

Water/Steam

Pentane

Toluene.

10. A pressurized fluid that actuates a machine is called as working fluid.

a) True

b) False

Answer: a

Explanation: A pressurized fluid that actuates a machine is called as working fluid.

This set of Steam and Gas Turbines Multiple Choice Questions & Answers  focuses on “Design of Nozzles”.

1. Nozzle is used to control direction or characteristics of flow.

a) True

b) False

Answer: a

Explanation: Nozzle is used to control the direction and characteristics of flow.

2. Nozzles are used to control the ___________

a) temperature

b) rate of flow

c) mass flow rate

d) none of the mentioned

Answer: b

Explanation: Nozzles are used to control the rate, speed, direction of flow.

3. A nozzle used to send fluid in coherent stream is called as ________

a) jet

b) high velocity nozzle

c) every nozzle sends fluid in coherent stream

d) none of the mentioned

Answer: a

Explanation: A nozzle used to send the fluid in coherent stream is called as jet.

4. In fountains the type of nozzle used is _______

a) none of the mentioned

b) turbulent jet

c) high speed nozzle

d) laminar jet

Answer: d

Explanation: Laminar jet nozzle is used to convert the fluid in laminar flow.

5. Nozzles used in blast furnaces are called as _______

a) jet

b) hot blast

c) tuyeres

d) none of the mentioned

Answer: c

Explanation: Nozzles used in blast furnaces are called tuyeres.

6. If mach number is less than one then its flow is ______________

a) subsonic flow

b) turbulent flow

c) laminar flow

d) none of the mentioned

Answer: a

Explanation: If M<1 then it is subsonic flow.

7. Nozzle used in rocket engine is __________

a) convergent nozzle

b) divergent nozzle

c) convergent – Divergent nozzle

d) none of the mentioned

Answer: c

Explanation: In rocket air flows from convergent section first and then from divergent section.

8. In rocket engine the flow in the throat of the nozzle is __________

a) subsonic

b) laminar

c) turbulent

d) none of the mentioned

Answer: a

Explanation: In the throat of nozzle mach number is less than one which indicates the flow is subsonic.

9. When mach number is greater than one the flow is ________

a) subsonic

b) supersonic

c) laminar

d) none of the mentioned

Answer: b

Explanation: When M>1 the flow is supersonic.

10. In rocket engines the amount of expansion in Nozzle determines the __________

a) exit temperature

b) exit pressure

c) exit temperature & pressure

d) none of the mentioned

Answer: c

Explanation: When the flow is subsonic, air in nozzle expands isoentropically and hence exit temperature and exit pressure depends on the amount of expansion.

This set of Steam and Gas Turbines Multiple Choice Questions & Answers  focuses on “Critical Pressure Ratio”.

1. Pressure ratios below 20 are used in _____________ engines.

a) steam turbine

b) aero derivative engines

c) heavy frame engines

d) none of the mentioned

Answer: c

Explanation: Lower pressure ratios are maintained in heavy frame engines.

2. Heavy frame engines are physically ___________

a) medium

b) large

c) small

d) none of the mentioned

Answer: b

Explanation: Heavy frame engines are physically large.

3. Aeroderivative engines have pressure ratios ___________

a) greater than 30

b) lesser than 30 and greater than 20

c) greater than 50

d) none of the mentioned

Answer: a

Explanation: Higher pressure ratios of greater than 30 are used in aeroderivative engines.

4. Aeroderivative engines are used where ____________ power units are required.

a) larger

b) smaller

c) optimum

d) none of the mentioned

Answer: b

Explanation: Aeroderivative engines are used where smaller power units are required.

5. Aeroderivative engines are larger.

a) True

b) False

Answer: b

Explanation: Aeroderivative engines are compact and smaller in size.

6. Aeroderivative engines release higher emissions.

a) True

b) False

Answer: a

Explanation: Aeroderivative engines are smaller and produce high output as a result of which they release higher emissions.

7. Gas turbines operate at pressures ________ than critical pressure ratio.

a) higher

b) lesser

c) does not depend on pressure ratio

d) none of the mentioned

Answer: b

Explanation: Gas turbines operate at pressures less than critical pressure ratio.

8. Critical pressure ratio is ratios of pressures at _________ discharge.

a) minimum

b) none of the mentioned

c) optimum

d) maximum

Answer: d

Explanation: Critical pressure ratio is the ratios of pressure at maximum discharge.

9. Ratio of critical pressure to inlet pressure in known as ___________

a) none of the mentioned

b) pressure ratio

c) critical pressure ratio

d) isoentropic pressure ratio

Answer: c

Explanation: Ratio of critical pressure to inlet pressure is called as critical pressure ratio.

10. In De Laval Nozzle critical pressure ratio is given by ^.

a) True

b) False

Answer: a

Explanation: Critical pressure ratio of De Laval nozzle is derived theoretically.

This set of Steam and Gas Turbines Multiple Choice Questions & Answers  focuses on “Nozzle Losses and Shock Waves”.

1. Coefficient of velocity of nozzle is _______________

a) theoretical velocity/Actual velocity

b) actual velocity/Theoretical velocity

c) it is an experimental value

d) none of the mentioned

Answer: b

Explanation: Coefficient of velocity is the ratio of actual velocity to theoretical velocity.

2. Coefficient of discharge of Nozzle is _______

a) Cd = Cc/Cv

b) Cd = Cc*Cv

c) Cd = Cv/Cc

d) None of the mentioned

Answer: b

Explanation: Coefficient of discharge is the product of coefficient of velocity and coefficient of contraction.

3. Coefficient of contraction is the__________

a) ratio of Actual cross sectional area to geometric cross sectional area

b) ratio of geometric cross sectional area to actual cross sectional area

c) ratio of pressure exerted to cross sectional area

d) none of the mentioned

Answer: a

Explanation: Coefficient of contraction is the factor with which the fluid contracts inside the nozzle.

4. Viscous losses takes place in nozzle.

a) False

b) True

Answer: b

Explanation: Velocity coefficient is included because of viscous losses in nozzle.

5. Momentum loss takes place in Nozzle.

a) True

b) False

Answer: a

Explanation: When fluid is transferring from convergent to divergent or reverse then its momentum might be lost.

6. Pressure loss occurs in nozzle due to __________

a) due to viscous force

b) when fluid flows from convergent to divergent

c) frictional forces

d) none of the mentioned

Answer: c

Explanation: Pressure losses occurs when fluid flows from convergent to divergent.

7. Head loss in nozzles occurs due to __________

a) pipes head loss

b) pressure loss

c) friction loss

d) none of the mentioned

Answer: a

Explanation: Head losses in nozzles are due to pipelines.

8. Minimum jet area that can be visible downstream is called vena contracta.

a) False

b) True

Answer: b

Explanation: Vena contrata is the minimum jet area visible down stream.

9. Viscous effect of fuel is measured in terms of __________

a) Nusselt’s number

b) Prandtl number

c) Reynold’s number

d) None of the mentioned

Answer: c

Explanation: Reynold’s number is the measure of viscous force.

10. At vena contracta the velocity is _________ and pressure is ___________

a) lowest, highest

b) highest, highest

c) highest, lowest

d) none of the mentioned

Answer: c

Explanation: At vena contracta the velocity will be highest and its pressure will be lowest.

11. When flow converts from supersonic to subsonic then __________ is produced.

a) shock wave

b) pressure drop

c) shock wave & pressure drop

d) none of the mentioned

Answer: a

Explanation: Shock waves are produced when flow changes suddenly from supersonic to subsonic.

12. Shock wave causes instantaneous _________ to the subsonic speed.

a) increase

b) decrease

c) remains constant

d) none of the mentioned

Answer: b

Explanation: Shock waves are produced due to more back pressures which indirectly reduces the subsonic speeds.

13. Region of supersonic acceleration is ________ by shock wave.

a) terminated

b) increased

c) decreased

d) none of the mentioned

Answer: a

Explanation: Due to shock waves subsonic speeds are decreased hence terminating the supersonic region.

This set of Steam and Gas Turbines Multiple Choice Questions & Answers  focuses on “Divergence and Position Angles”.

1. Jet engines can be accelerated to supersonic velocities with _______ section.

a) Convergent

b) Divergent

c) Does not depend on shape of the section

d) None of the mentioned

Answer: b

Explanation: When fluid passes through divergent section maximum thrust force is provided so that jet engines can be accelerated to supersonic velocities.

2. Nozzles with high pressure ratios have ______ area divergent sections.

a) variable

b) constant

c) maximum

d) none of the mentioned

Answer: a

Explanation: When nozzles are operated at high pressure ratios it needs variable divergent sections because each pressure ratio requires a special divergent section.

3. In nozzle the gases expand _________

a) Iso-thermally

b) Iso-entropically

c) Adiabatically

d) None of the mentioned

Answer: c

Explanation: No heat loss takes place when gases are expanded in nozzle and hence it is said that gases expand adiabatically in nozzle.

4. Convergent nozzles are used in jet engines upto nozzle pressure ratio of _______

a) 0.8

b) 1.8

c) 2

d) none of the mentioned

Answer: b

Explanation: Convergent nozzles are used until the nozzle pressure ratio is 1.8. If the nozzle pressure ratio goes above 1.8 then convergent nozzle will choke.

5. Convergent divergent nozzles used in rocket engines have _________ area ratio.

a) higher

b) lower

c) optimum

d) none of the mentioned

Answer: a

Explanation: Convergent divergent nozzles used in rocket engines have high pressure ratio.

6. Over expansion occurs when exit area of nozzle is _________ than primary nozzle.

a) equal

b) smaller

c) greater

d) none of the mentioned

Answer: c

Explanation: When exit area of nozzle is greater than primary nozzle then fluid suddenly expands leading to over expansion.

7. When divergent section is added _________

a) exhaust velocity is increased

b) exhaust temperature is increased

c) exhaust pressure is increased

d) none of the mentioned

Answer: a

Explanation: When divergent section is added exhaust velocity is increased.

8. What happens when nozzle doesn’t open after the burner is on?

a) None of the mentioned

b) Thrust force decreases

c) Exit velocity increases

d) Turbine blades get overheat and fails

Answer: d

Explanation: When nozzle doesn’t open, turbine blades get overheated and fails.

9. What happens to mach number when divergence angle is 4 degrees?

a) Mach number drops from 1.10 to 0.45

b) Mach number drops from 2.10 to 1.45

c) Mach number drops from 3.10 to 2.25

d) None of the mentioned

Answer: b

Explanation: It was an experimental value obtained from CFD analysis.

10. What happens to mach number when divergence angle is 7 degrees?

a) Mach number drops from 2.5 to 1.5

b) Mach number drops from 3 to 2

c) Mach number drops from 1.5 to 1

d) None of the mentioned

Answer: a

Explanation: It was an experimental value obtained from CFD analysis.

This set of Steam and Gas Turbines Multiple Choice Questions & Answers  focuses on “Wet and Supersaturated Steam”.

1. Mixture of steam and liquid water is called as _________

a) dry steam

b) wet steam

c) saturated steam

d) none of the mentioned

Answer: b

Explanation: Mixture of steam and liquid water is called as wet steam. Where as dry steam is boiled steam and sometimes dry steam is also called as saturated steam.

2. Supersaturated steam is also called as _________

a) saturated steam

b) single phase mix

c) two phase mix

d) none of the mentioned

Answer: c

Explanation: In supersaturated steam there is a mixture of two phases gaseous and liquid, so it is called a two phase mix.

3. If heat is added to the wet steam temperature _________

a) raises immediately

b) decreases immediately

c) raises after sometime

d) none of the mentioned

Answer: c

Explanation: When heat is added to the steam immediately the liquid particles try to evaporate and form saturated steam only after that the temperature starts rising.

4. After steam bubbles break the water surface, they carry water droplets this is called as ________

a) entrainment

b) capillarity

c) reverse capillarity

d) none of the mentioned

Answer: a

Explanation: When steam bubbles break water surface they carry some water droplets. This process is called as entrainment.

5. Entrainment happens at __________

a) liquid surface having contact with atmosphere

b) outlet of the boiler

c) inlet of the boiler

d) none of the mentioned

Answer: b

Explanation: Entrainment happens at the outlet of the boiler.

6. Hydraulic water hammer is caused by _______

a) wet steam

b) dry steam

c) pressurized water

d) none of the mentioned

Answer: a

Explanation: Hydraulic water hammer is caused by wet steam.

7. Hydraulic water hammer is caused due to ______

a) humidity in pipelines

b) accumulation of condensate

c) humidity in pipelines & accumulation of condensate

d) none of the mentioned

Answer: c

Explanation: Hydraulic water hammer is caused due to humidity on pipelines or accumulation of condensate.

8. Resistance of water dominating the steam is called as _______

a) hydraulic water hammer

b) erosion

c) contamination

d) none of the mentioned

Answer: b

Explanation: Resistance of water hammer dominating steam is called erosion.

9. When steam is transported dryness fraction _________

a) increases

b) decreases

c) remains constant

d) none of the mentioned

Answer: b

Explanation: When steam travels in pipeline its dryness fraction increases.

10. Wet steams causes corrosion.

a) True

b) False

Answer: a

Explanation: Wet steam may cause

corrosion

erosion

hydraulic water hammer in pipelines

destroy turbine blades etc.

This set of Steam and Gas Turbines Inteview Questions and Answers for freshers focuses on “Nozzle Discharge Coefficients and Calculations”.

1. Coefficient of discharge is the __________ of Actual discharge to the theoretical discharge.

a) ratio

b) product

c) sum

d) none

Answer: a

Explanation: Discharge coefficient is the ratio of actual discharge to the theoretical discharge.

2. Coefficient of discharge is used to measure ___________

a) none of the mentioned

b) pressure exerted by the nozzle on the fluid

c) flow rate allowed by the nozzle

d) resistance offered by the nozzle

Answer: d

Explanation: Coefficient of discharge is used to measure the inaccountable losses of the fluid passing through the nozzle. It is used to measure the resistance exerted by the nozzle.

3. Unit of flow resistance is _________

a) N/m 2

b) m 2 /N

c) KN/Kg

d) No unit

Answer: d

Explanation: Flow resistance is a unit less parameter.

4. Coefficient of discharge is the ____________

a) product of coefficient of velocity and coefficient of contraction

b) arithmetic sum of coefficient of velocity and coefficient of contraction

c) ratio of coefficient of velocity and coefficient of contraction

d) none of the mentioned

Answer: a

Explanation: Cd = Cc*Cv

Where

Cd = Coefficient of discharge

Cc = Coefficient of contraction

Cv = Coefficient of velocity.

5. Coefficient of discharge is _____________

a) directly proportional to coefficient of discharge

b) inversely proportional to square of the coefficient of discharge

c) inversely proportional to coefficient of discharge

d) directly proportional to square of coefficient of discharge

Answer: b

Explanation: Coefficient of resistance is denoted by K and coefficient of discharge is denoted by Cd. Where

K = 1 /Cd 2 .

6. For sharp edge orifice, coefficient of discharge lies between ___________

a) 0.61 – 0.64

b) 0.87 – 0.89

c) 0.50 – 0.61

d) none of the mentioned

Answer: a

Explanation: For sharp edges coefficient of discharge lies between 0.61 – 0.64.

7. Coefficient of discharge  can be written as Cd=1/K  .

a) True

b) False

Answer: a

Explanation: Coefficient of discharge is inversely proportional to square root of K.

8. In the equation Cd=1/K  what does K mean ?

a) Pressure drop inside the nozzle

b) Mass flow rate

c) Flow resistance

d) None of the mentioned

Answer: c

Explanation: Coefficient of discharge is inversely proportional to square root of flow resistance.

9. Coefficient of discharge is inversely proportional to square root of _______

a) flow resistance

b) pressure drop inside the nozzle

c) none the mentioned

d) flow resistance & pressure drop inside the nozzle

Answer: d

Explanation: Coefficient of discharge can also be written as Cd = m/*Area)  or else Cd = 1/K  .

10. Coefficient of discharge is directly proportional to mass flow rate.

a) True

b) False

Answer: a

Explanation: When mass flow rate increases coefficient of discharge increases.

This set of Steam and Gas Turbines Multiple Choice Questions & Answers  focuses on ” Design of Turbine Flow Passages”.

1. A turbine having alternate blades and nozzles is called as _______________

a) Impulse turbine

b) Reaction turbine

c) Impulse & Reaction turbine

d) None of the mentioned

Answer: a

Explanation: When blades and nozzles are arranged in alternate manner pressure loss can be reduced and hence it is called an impulse turbine.

2. Multi stage arrangement of turbines is called as __________

a) Impulse turbine

b) Reaction turbine

c) Compounding

d) None of the mentioned

Answer: c

Explanation: Multi stage arrangement of turbines reduces the pressure loss and velocity losses and hence it is called as compounding.

3. Compounding __________ efficiency at low speed.

a) decrease

b) increase

c) maximizes

d) none of the mentioned

Answer: b

Explanation: Even at low speeds velocity wastage is prevented and hence efficiency is increased.

4. In pressure compounded turbines moving nozzles are followed by turbine blades.

a) True

b) False

Answer: b

Explanation: In pressure compounding fixed nozzles are followed by moving blades.

5. In pressure compounded turbines flow passage is from ______________

a) moving nozzles to fixed blades

b) fixed nozzles to moving blades

c) fixed blades to moving nozzles

d) none of the mentioned

Answer: b

Explanation: In pressure compounded turbines pressure drop is reduced into stages reducing the pressure loss and hence increasing the efficiency. Hence in pressure compounded turbines flow passage if from fixed nozzles to moving blades.

6. In velocity compounded turbines flow passage is from ____________

a) moving blades to fixed nozzles

b) fixed nozzles to moving blades

c) fixed blades to moving nozzles

d) none of the mentioned

Answer: d

Explanation: In velocity compounded turbines velocity drop is maintained in stages and hence reducing velocity loses. Hence in velocity compounded turbines flow passage is from fixed nozzles to multiple rows of moving blades alternating with fixed blades.

7. A velocity compounded impulse turbine is also called as __________

a) Curtis wheel

b) Pressure compounded

c) Curtis wheel & Pressure compounded

d) None of the mentioned

Answer: a

Explanation: Velocity compounded turbines are invented by a scientist called Curtis and hence it is named after his name.

8. Reaction turbine is also called as _________

a) Impulse turbine

b) Curtis wheel

c) Parsons turbine

d) None of the mentioned

Answer: c

Explanation: Reaction turbine was invented by a scientist names Parson and hence it was named after his name.

9. A turbine comprising of fixed blades and moving nozzles is called as reaction turbines.

a) True

b) False

Answer: a

Explanation: In reaction turbines the reaction produced when steam hits the turbine is also utilized to produce power output.

10. Compounding is used for _________ power applications.

a) low

b) high

c) medium

d) none of the mentioned

Answer: b

Explanation: In compounding high powers are produced at low speeds also. Hence for low power production compounding need not be used.

This set of Steam and Gas Turbines Multiple Choice Questions & Answers  focuses on “Energy Distribution and Effect of Carry Over Velocity”.

1. Most of the energy produced by gas turbine is utilized by _______

a) compressor

b) condenser

c) to drive turbine blade

d) none of the mentioned

Answer: a

Explanation: Two third of the energy produced by gas turbine is utilized by the compressor to compress the air.

2. In gas turbines during expansion rotor’s blades rotate, which is an __________ transformation.

a) reversible

b) irreversible

c) no energy transformation occurs by rotation of rotor blades

d) none of the mentioned

Answer: b

Explanation: Rotation of rotor blades is an irreversible transformation.

3. Energy losses in gas turbines are __________

a) flue gasses energy loss

b) rotational loss

c) flue gasses energy & rotational loss

d) none of the mentioned

Answer: c

Explanation: Flue gases loss and rotational loss are some of the energy losses in gas turbine.

4. In steam turbines carry over losses are due to _____________

a) formation of eddies in annular spaces

b) decrease in pressure

c) increase in temperature

d) none of the mentioned

Answer: a

Explanation: Carry over losses are due to formation of eddies in steam turbines.

5. Corrosion and Erosion takes place if dryness factor of steam is __________ in last stage.

a) less than 0.68

b) more than 0.60

c) less than 0.88

d) none of the mentioned

Answer: c

Explanation: Liquid particles have lesser velocity than steam particles and hence if dryness fraction is less than 0.88 even erosion and corrosion can takes place.

6. Radiation losses can be covered by _______

a) decreasing the temperature of steam

b) proper insulation

c) decreasing the temperature of steam and proper insulation

d) none of the mentioned

Answer: b

Explanation: Radiation and convention losses can be reduced by proper insulation.

7. Enthalpy __________ takes place when steam enters from turbine to condenser.

a) decrease

b) increase

c) depends on the situation

d) none of the mentioned

Answer: a

Explanation: When steam leaving turbine has kinetic energy and when it enters condenser enthalpy loss takes place.

8. Energy balance states that total energy input is equal to arithmetic sum of Energy losses, output work, flue gasses loss and rotational loss.

a) True

b) False

Answer: a

Explanation: Energy balance equation states that

Total energy input = Energy output + energy losses + flue gasses loss + rotational loss.

9. ______________ is commonly called as carry over velocity.

a) Compressor velocity

b) Inlet velocity

c) Exit velocity

d) None of the mentioned

Answer: c

Explanation: Velocity at exit is called carryover velocity.

10. Carryover loss is also called a leaving loss.

a) True

b) False

Answer: a

Explanation: Loss in exit velocity is called carryover loss or leaving loss.

This set of Steam and Gas Turbines Questions for entrance exams focuses on “Requirements for Radial Equilibrium and Velocity Diagrams”.

1. For radial equilibrium axial flow is assumed.

a) True

b) False

Answer: b

Explanation: For radial equilibrium asymmetrical flow is assumed.

2. For radial equilibrium constant velocity is assumed.

a) True

b) False

Answer: a

Explanation: For radial equilibrium meridional velocity is assumed to be constant.

3. For simple radial equilibrium it is assumed that ______________

a) r*Vu = constant

b) r/Vu = constant

c) Vu/r = constant

d) None of the mentioned

Answer: a

Explanation: For a free vortex in a radial equilibrium it is assumed that the product of radius and velocity has remained as constant.

4. Secondary losses are caused due to _________

a) frictional forces

b) lift force induced in turbine

c) drag force induced by secondary force

d) none of the mentioned

Answer: c

Explanation: Secondary losses are caused due to drag forces induced by secondary forces.

5. For radial equilibrium it is assumed that viscosity is __________

a) high

b) negligible

c) low

d) none of the mentioned

Answer: b

Explanation: For radial equilibrium the flow is assumed to be asymmetrical and viscous forces are assumed to be negligible.

6. In radial equilibrium method blade force is assumed to be ____________

a) high

b) low

c) zero

d) none

Answer: c

Explanation: Blade forces are assumed to be zero in radial equilibrium.

7. For radial equilibrium it is assumed that heat transfer is ____________

a) zero

b) high

c) low

d) none

Answer: a

Explanation: For radial equilibrium it is assumed that the flow is non viscous flow and heat transfer is zero.

8. For radial equilibrium entropy term is _________

a) high

b) low

c) neglected

d) none of the mentioned

Answer: c

Explanation: For radial equilibrium method entropy term is neglected.

9. For radial equilibrium it is assumed that the steam lines are ___________ to the axis line.

a) perpendicular

b) parallel

c) inclined

d) none of the mentioned

Answer: b

Explanation: For radial equilibrium it is assumed that the steam lines are axis parallel and have no inclination.

10. For radial equilibrium friction is neglected.

a) True

b) False

Answer: a

Explanation: Friction is neglected in radial equilibrium.

This set of Steam and Gas Turbines Test focuses on “Elements of Airfoil, Single Airfoil Principle and Limitations”.

1. Shape of a wing or blade as seen from top view is called as airfoil.

a) True

b) False

Answer: b

Explanation: Shape of a wing or blade as seen from cross section is called as airfoil.

2. Airfoil can also be called as ________

a) aerofoil

b) propeller

c) sail

d) none of the mentioned

Answer: a

Explanation: Airfoil can also be called as Aerofoil.

3. When airfoil shape moves through fluid it produces __________

a) Thrust force

b) Drag force

c) Aerodynamic force

d) None of the mentioned

Answer: c

Explanation: When an airfoil shape is moved through a fluid it produces aerodynamic forces. The rest thrust and drag forces are the components of the aerodynamic force.

4. The lift to the airfoil is mainly the result of ______________

a) angle of attack

b) shape

c) angle of attack & shape

d) none of the mentioned

Answer: c

Explanation: The lift caused by the airfoil is primarily the result of angle of attack and shape.

5. Cambered airfoil generates lift at _________ angle of attack.

a) high

b) low

c) zero

d) none of the mentioned

Answer: c

Explanation: Cambered airfoil can generate lift at zero angle of attack whereas other airfoils require positive angle of attack.

6. For an airfoil fluid velocity will be ______ on upper surface when compared to lower surface.

a) higher

b) lower

c) equal

d) none of the mentioned

Answer: a

Explanation: As pressure is high on the upper surface than lower surface, through Bernoulli’s principle velocity is also high on the upper surface when compared to lower surface.

7. The lift force is directly proportional to _________

a) difference in the pressure between upper and lower surfaces

b) difference in the velocity between upper and lower surfaces

c) difference in the pressure & velocity between upper and lower surfaces

d) none of the mentioned

Answer: c

Explanation: The lift force is directly proportional to the pressure difference between the upper and lower surfaces and from Bernoulli’s principle it is also directly proportional to difference in the velocities between upper and lower surfaces.

8. Elements of airfoil are _________

a) Slats

b) Flaps

c) Slats & Flaps

d) None of the mentioned

Answer: c

Explanation: Basic elements of airfoil consists of slats and flaps.

9. To increase the lift at given angle of attack _______ are used.

a) Slats

b) Flaps

c) Cannot be increased

d) None of the mentioned

Answer: b

Explanation: Flaps are used to increase the lift at given angle of attack.

10. Increase in angle of attack can be done by ________

a) Slats

b) Governor mechanism

c) Flaps

d) None of the mentioned

Answer: c

Explanation: Angle of attack can be increased by slats.

This set of Steam and Gas Turbines Multiple Choice Questions & Answers  focuses on “Cascade Principle”.

1. Arrangement of blades in an order to represent the blade ring in Turbo machinery is called as cascade.

a) True

b) False

Answer: a

Explanation: Cascade is an array of blades to represent the blade ring in turbo machinery.

2. Cascades __________ the efficiency.

a) decreases

b) increases

c) does not effect

d) none

Answer: b

Explanation: Cascades are introduced to improve the efficiency.

3. When steam is passed through the cascade the direction of air __________

a) reverse

b) remains the same

c) turned

d) cascade is nowhere related to direction

Answer: c

Explanation: When steam is passed through cascade its direction is reversed.

4. Across the turbine cascade static pressure _________

a) drops

b) increases

c) remains same

d) none of the mentioned

Answer: a

Explanation: Across the turbine cascade the static pressure drops.

5. Due to the formation of boundary layers on blades friction losses _________

a) remains the same

b) decreases

c) increases

d) none of the mentioned

Answer: c

Explanation: Due to the formation of boundary layers frictional losses increase due to viscous forces.

6. In compressor cascade when internal pressure is lost ____________

a) axial force is gained

b) axial force is reduced

c) efficiency reduces

d) none of the mentioned

Answer: a

Explanation: In compressor cascade when internal pressure is lost axial force is developed.

7. Drag force is parallel to lift force.

a) True

b) False

Answer: b

Explanation: Drag force is always perpendicular to lift force.

8. Due to viscosity lift force is __________

a) increased

b) decreased

c) remains constant

d) none

Answer: b

Explanation: Due to viscosity lift force is decreased.

9. Due to turbine cascade the drag ________ the lift.

a) increases

b) decreases

c) does not change

d) none of the mentioned

Answer: a

Explanation: Due to turbine cascade drag contributes some useful work which increases the lift.

10. Due to compressor cascade, the static pressure is __________

a) reduced

b) does not change

c) increased

d) none of the mentioned

Answer: c

Explanation: Due to compressor cascade viscous force decreased and hence static pressure is also decreased.

This set of Steam and Gas Turbines Multiple Choice Questions & Answers  focuses on “Relationship between Velocity Ratios”.

1. Velocity ratio is represented by ___________

a) Alpha

b) Beta

c) Sigma

d) None of the mentioned

Answer: c

Explanation: Velocity ratio is represented by sigma.

2. For single stage impulse turbine optimum sigma value lies between ____________

a) 0.4 and 0.6

b) 0.2 and 0.4

c) 0.1 and 0.3

d) none of the mentioned

Answer: a

Explanation: 0.4 and 0.6 are the boundary values for sigma in single stage impulse turbine which can be found from graph plotted between sigma and efficiency.

3. For two stage impulse turbine optimum sigma value lies between __________

a) 0.3 and 0.5

b) 0.2 and 0.4

c) 0.1 and 0.5

d) none of the mentioned

Answer: b

Explanation: For two stage impulse turbine sigma value lies in between 0.2 and 0.4 which can be found out from graph plotted between sigma value and efficiency.

4. For reaction turbines the optimum sigma value lies between _____________

a) 0.8 and 1.0

b) 0.6 and 1.0

c) 0.4 and 0.8

d) none of the mentioned

Answer: a

Explanation: For reaction turbines sigma value lies between 0.8 and 1.0 which can be found out from graph plotted between sigma and efficiency.

5. Speed of the blade to speed of the gas ratio can be denoted by ___________

a) Alpha

b) Sigma

c) Gamma

d) None of the mentioned

Answer: b

Explanation: Blade to gas speed ratio is known as velocity ratio and it can be represented by sigma.

6. Best velocity ratio for four row impulse turbine is ________

a) one seventh

b) one sixth

c) half

d) none of the mentioned

Answer: a

Explanation: The best velocity ratio for four row impulse turbine is one seventh.

6. Efficiency of the four row impulse turbine with a velocity ratio of one seventh is ______

a) 55%

b) 44%

c) 34%

d) 77%

Answer: b

Explanation: Efficiency of four row impulse turbine with a velocity of one seventh is 44% which was found from graph plotted against efficiency and velocity ratio.

7. Velocity ratio is the integral of ________ of the velocity in each row.

a) fourth power

b) cube

c) square

d) none of the mentioned

Answer: c

Explanation: Velocity ratio is the integral of square of velocity in each row.

8. Velocity ratio is directly proportional to square of velocity.

a) True

b) False

Answer: b

Explanation: Velocity ratio is directly proportional to integral of square of velocity in each row.

9. When velocity in each row increases its velocity ratio __________

a) decreases

b) remains constant

c) increases

d) none

Answer: c

Explanation: When velocity in each row increases its velocity ratio also increases.

10. Velocity ratio is directly proportional to velocity in each row.

a) True

b) False

Answer: b

Explanation: Velocity in each row is inversely proportional to velocity ratio.

This set of tough Steam and Gas Turbines questions and answers focuses on “Turbine Rotor and Blade Stresses”.

1. Thermal stresses in rotor is ___________ than in cylinder.

a) lesser

b) greater

c) equal

d) none

Answer: b

Explanation: Pressure and Temperature are higher in high pressure cylinders and hence thermal stress in rotor is higher than that in cylinder.

2. Crank Nicholson method is an integration method.

a) True

b) False

Answer: a

Explanation: Crank Nicholson method is an integration method.

3. Westinghouse formula is used to calculate ____________ formula.

a) heat transfer

b) efficiency

c) heat transfer & efficiency

d) none of the mentioned

Answer: c

Explanation: Westinghouse formula is used to calculate heat transfer formula where heat transfer is to be found in third dimension.

4. Nagong-Haqi formula is used to calculate ___________ formula.

a) heat transfer

b) efficiency

c) heat transfer & efficiency

d) none of the mentioned

Answer: a

Explanation: Both westinghouse formula and nagong-haqi formula are used to calculate heat transfer formula.

5. Stress in the rotor is influenced by ______

a) Pressure

b) Temperature

c) Force

d) None of the mentioned

Answer: b

Explanation: Stress in rotor is influenced by temperature field.

6. When pulling stress and mechanical stress in same direction _______

a) Turbine efficiency decreases

b) Turbine shutdowns

c) Turbine slows down

d) None of the mentioned

Answer: d

Explanation: When pulling stress and mechanical stress in same direction, turbine shutdowns.

7. Turbine blades are subjected to stress from ___________

a) centripetal force

b) centrifugal force

c) centripetal & centrifugal force

d) none of the mentioned

Answer: b

Explanation: Turbine blades are subjected to stress from centrifugal forces.

8. Turbine blades are conventionally casted.

a) True

b) False

Answer: a

Explanation: Turbine blades can be conventionally casted.

9. In atomic scale shear stress varies ___________

a) tangentially & sinusoidally

b) tangentially

c) sinusoidally

d) none of the mentioned

Answer: c

Explanation: When shear stress in noted in atomic scale is varies sinusoidally.

10. Ductility increases with ____________ in temperature.

a) Increase

b) Decrease

c) Ductility doesn’t effect with temperature

d) None of the mentioned

Answer: a

Explanation: Ductility increases with an increase in temperature.

This set of Steam and Gas Turbines Multiple Choice Questions & Answers  focuses on “Bending Stresses and Vibration”.

1. Vibration in rotor blades causes ________________

a) resonance

b) shut down of turbine

c) resonance & shut down of turbine

d) none of the mentioned

Answer: a

Explanation: When any particles vibrates with the same frequency as of natural frequency then it resonates.

2. Stresses are divided into ____________

a) Steady stress

b) Unsteady stress

c) Steady & Unsteady stress

d) None of the mentioned

Answer: c

Explanation: Stresses are divided into two types. They are

Steady stresses

Unsteady stresses.

3. Stress caused due to thermal loading is classified under ______

a) Steady stress

b) Unsteady stress

c) Breakage

d) None of the mentioned

Answer: a

Explanation: Stresses caused due to centrifugal forces, loading, thermal causing are classified into steady state stresses.

4. Stresses caused due to centrifugal forces are classified into unsteady state stresses.

a) True

b) False

Answer: b

Explanation: Stresses caused due to centrifugal forces are classified into steady stresses.

5. Unsteady stresses are caused due to interaction of rotating blades with ___________

a) Stationary feature

b) Viscous force

c) Friction

d) None of the mentioned

Answer: a

Explanation: Unsteady stresses are caused due to interaction of rotating blade with stationary features.

6. When working temperature is increased its rupture stress is ___________

a) Increased

b) Decreased

c) Working temperature is not related with rupture stress

d) None of the mentioned

Answer: b

Explanation: Increase in working temperature is associated with decrease in rupture stress.

7. In general, there are ______ types of stresses.

a) 2

b) 4

c) 3

d) None of the mentioned

Answer: c

Explanation: Stresses are classified into three types. They are

centrifugal stress

gas bending stress

centrifugal bending stress.

8. Centrifugal stress is a ________

a) shear stress

b) tensile stress

c) lateral stress

d) none of the mentioned

Answer: b

Explanation: Centrifugal stress is a tensile stress.

9. Centrifugal stress depends upon __________

a) Hub to tip ratio

b) Blade rotating speed

c) Hub to tip ratio & Blade rotating speed

d) None of the mentioned

Answer: c

Explanation: Centrifugal stress depends upon

blade density

hub to tip ratio

blade tip speed.

10. Centrifugal stress depends upon blade density.

a) True

b) False

Answer: a

Explanation: Centrifugal stresses depends upon

blade density

hub to tip ration

blade tip speed.

This set of Steam and Gas Turbines Multiple Choice Questions & Answers  focuses on “Disk Stresses and Blade Fastening”.

1. Rotating disks are subjected to _______

a) mechanical stress

b) thermal stress

c) mechanical & thermal stress

d) none of the mentioned

Answer: c

Explanation: Rotating disks are subjected to both mechanical and thermal stresses.

2. Internal pressure on the disk are due to _______

a) broken fittings

b) expanded fittings

c) shrink fitted on its mountings

d) none of the mentioned

Answer: c

Explanation: Internal pressure on disk is caused due to shrink fitted on its mountings.

3. Finite element analysis is done for rotating disk.

a) True

b) False

Answer: a

Explanation: Different temperatures are established when hot gasses are passed and hence finite element analysis is done.

4. High stresses in rotating disks are caused due to _______

a) excessive temperature

b) excessive rotating speeds

c) excessive temperature & rotating speeds

d) none of the mentioned

Answer: b

Explanation: High stresses in rotating disks are caused due to excessive rotating speeds.

5. Rotational disks deform due to ______________

a) uni symmetrical

b) multi symmetrical

c) axi symmetrical

d) none of the mentioned

Answer: c

Explanation: Deformation of rotational disks is axi symmetrical.

6. Gas turbine discs are made of _______

a) Chromium

b) Chrome-Nickel steel alloy

c) Nickel

d) None of the mentioned

Answer: b

Explanation: Chrome-nickel steel alloy is used to make gas turbine discs in general.

7. Contact at fastening between blade root and disk staple is ________

a) one dimensional

b) two dimensional

c) three dimensional

d) none of the mentioned

Answer: c

Explanation: Three dimensional contact is maintained at fastening between blade root and disk staple.

8. Some of the fasteners are _______

a) Bolts

b) Nuts

c) Keys

d) All of the mentioned

Answer: d

Explanation: Keys, Nuts and Bolts are some fasteners in turbine generator steam turbines.

9. ________ are used to secure some fasteners which have tendency to slip or slide away.

a) Bolts

b) Nuts

c) Washers

d) None of the mentioned

Answer: c

Explanation: Washers are used to lock fasteners which slip or slide away.

10. Bolts are _______ fasteners.

a) locking fasteners

b) threaded fasteners

c) frictional fastener

d) none of the mentioned

Answer: b

Explanation: Bolts are threaded fasteners as they have threading on them.

This set of Steam and Gas Turbines Multiple Choice Questions & Answers  focuses on “Shrouding and Lacing Wires”.

1. Shrouding is used to _________ the damping effect.

a) increase

b) decrease

c) avoid

d) none of the mentioned

Answer: a

Explanation: Shrouding is used to increase the damping frequency.

2. Shrouding _______ blade flutter.

a) increases

b) reduces

c) doesn’t change

d) none of the mentioned

Answer: b

Explanation: Damping effect is increased due to shrouding and blade flutter is reduced.

3. Large electricity generating steam turbine uses shrouding.

a) True

b) False

Answer: a

Explanation: Shrouding is used in large electricity generating steam turbine.

4. Shrouding is done to _______ blades.

a) small

b) large

c) every

d) none of the mentioned

Answer: b

Explanation: Large blades use shrouding.

5. Shrouding is used for ________ pressure turbines.

a) medium

b) high

c) low

d) none of the mentioned

Answer: c

Explanation: Shrouding is used for large blades and low pressure turbines.

6. Shrouding is complemented with lacing wires.

a) True

b) False

Answer: a

Explanation: Shrouding is complemented with lacing wires for large blades and low pressure turbines.

7. Lace wires _______ blade flutter.

a) increases

b) reduces

c) doesn’t change

d) none of the mentioned

Answer: b

Explanation: Lacing wires are used to reduce blade flutter.

8. Shrouding can also be used for ________ pressure turbines.

a) medium

b) high

c) low

d) none of the mentioned

Answer: c

Explanation: Both low and high pressure turbines use shrouding.

9. When shrouding is not required it ____________

a) reduces the blade flutter

b) reduces the centrifugal load

c) reduces the blade flutter & centrifugal load

d) none of the mentioned

Answer: b

Explanation: When shrouding is not used it decreases the centrifugal load as the total load on the center of the turbine decreases.

10. When shrouding is not used cooling requirements are also reduced.

a) True

b) False

Answer: a

Explanation: Centrifugal load and the cooling requirements can be reduced by shroud less turbines.

This set of Steam and Gas Turbines Multiple Choice Questions & Answers  focuses on “Cooling of Gas Turbine Blades”.

1. Cooling is classified into ________

a) air cooling

b) liquid cooling

c) air & liquid cooling

d) none of the mentioned

Answer: c

Explanation: Cooling is of two types. They are

Air cooling

Liquid cooling.

2. Liquid cooling method has _______

a) high specific heat capacity

b) low specific heat capacity

c) low evaporative cooling

d) none of the mentioned

Answer: a

Explanation: Liquid cooling method has a high specific heat capacity.

3. In liquid cooling leakages are _________

a) increases

b) reduced

c) equal in both air and liquid cooling

d) none of the mentioned

Answer: b

Explanation: In liquid cooling leakages are reduced.

4. Quality of air required for air cooling is ______

a) 1-3 %

b) 2-5 %

c) above 5 %

d) none of the mentioned

Answer: a

Explanation: 1-3% air quality is required for air cooling.

5. By liquid cooling blade temperature can be reduced by ________

a) 300 – 400%

b) 200 – 300%

c) 100 – 500%

d) none of the mentioned

Answer: b

Explanation: Liquid cooling decreases blade temperature by 200-300%.

6. For air cooling,cooling air comes from _________

a) compressor

b) atmosphere

c) condenser

d) none of the mentioned

Answer: a

Explanation: In air cooling, cooling air comes from compressor.

7. In impingement cooling ___________

a) cooling is done by fins

b) by making air with high velocity to hit the blades

c) holes in the blades

d) none of the mentioned

Answer: b

Explanation: In impingement cooling method cooling is done my making air with high velocity to hit the blades.

8. In impingement cooling majority of cooling is done by ________

a) convection

b) conduction

c) radiation

d) none of the mentioned

Answer: a

Explanation: In impingement cooling majority of cooling is done by convection.

9. Impingement cooling is used for lesser loads of heating.

a) True

b) False

Answer: b

Explanation: Impingement cooling is done when lesser loads of cooling is done.

10. In cooling effusion blade surface is made of _______

a) porous material having small orifice

b) fins

c) with larger surface area

d) none of the mentioned

Answer: a

Explanation: In cooling effusion blade surface is made of porous material with small loads so that cooling is more efficiently done.

This set of Steam and Gas Turbines Multiple Choice Questions & Answers  focuses on “Casing and Metallurgical Considerations”.

1. Turbine casing controls _______________

a) working fluid

b) pressure

c) temperature

d) none of the mentioned

Answer: a

Explanation: Turbine casing can also control the working fluid.

2. Turbine casing also contains __________ working fluid.

a) temperature of

b) flow direction of

c) pressure

d) none of the mentioned

Answer: b

Explanation: Turbine casing contains the working fluid and also controls the direction of flow of it.

3. __________ is also used to direct the working fluid.

a) Guide vanes

b) Casing

c) Guide vanes & Casing

d) None of the mentioned

Answer: c

Explanation: Casing can control the working fluid which means it can direct the working fluid.

4. There is a possibility of leakage in between turbine rotor and ________

a) casing

b) valves

c) casing & valves

d) none of the mentioned

Answer: a

Explanation: As casing contains working fluid, there is a problem of leakage in between casing and turbine rotor.

5. In Tandem compound casing a _________ casing are directly coupled together to a generator.

a) single

b) multiple

c) two

d) none of the mentioned

Answer: b

Explanation: In tandem compound casing two or more casings are coupled together to a driven generator.

6. In single casing, Casing is directly coupled to a _____________

a) generator

b) combustor

c) generator & combustor

d) none of the mentioned

Answer: a

Explanation: In single casing, casing is directly coupled to a turbine generator.

7. Cross compounded turbines are used for __________ applications.

a) smaller

b) larger

c) medium

d) none of the mentioned

Answer: b

Explanation: Cross compounded turbines are used for larger applications.

8. Double exhaust rotors have ________ pressure casings.

a) high

b) low

c) medium

d) none of the mentioned

Answer: b

Explanation: Double exhaust rotors use low pressure casings.

9. Two flow rotors use __________ pressure casings.

a) low

b) high

c) medium

d) none of the mentioned

Answer: a

Explanation: Two flow rotors use low pressure casings.

10. In a steam turbine a set of ________ blades are connected to casing.

a) stationary

b) rotating

c) stationary & rotating

d) none of the mentioned

Answer: b

Explanation: In a steam turbine a set of stationary blades are connected to casing.

11. With metallurgical considerations the temperature in Gas turbine blades is reduced by ________

a) 2000 F

b) 3000 F

c) 1000 F

d) none of the mentioned

Answer: a

Explanation: Due to metallurgical consideration the temperature of turbine blades is reduced by 2000F.

12. Due to metallurgical consideration in closed cycle cooling system the upper temperature is limited to _____________

a) 500 C

b) 540 C

c) 200 C

d) none of the mentioned

Answer: b

Explanation: Due to metallurgical consideration in a closed cycle cooling system upper limit is fixed to 540 C.

13. Due to metallurgical consideration _____________ can be limited.

a) pressure

b) volume

c) temperature

d) none of the mentioned

Answer: c

Explanation: Temperature can be limited by metallurgical considerations.

14. For continuous operation in elevated temperature ______________ cooled materials are used for blades.

a) Ceramic

b) Ceramic and liquid

c) Liquid

d) None of the mentioned

Answer: b

Explanation: For continuous operation in elevated temperatures ceramic and liquid cooled materials are used for turbine blades.

15. Metallurgical considerations ________________ the material can bare which is used to manufacture blades.

a) maximum temperature

b) maximum pressure

c) maximum temperature & pressure

d) none of the mentioned

Answer: c

Explanation: Metallurgical consideration define the maximum temperature and pressure the metal can bare which is used to manufacture the blade.

This set of Steam and Gas Turbines Multiple Choice Questions & Answers  focuses on “Impulse Turbine Blade Profile”.

1. A ___________ drawn from the head of turbine blade to tail is called as chord.

a) straight line

b) curved axis

c) linear axis

d) none of the mentioned

Answer: a

Explanation: In blade profiles chord is a straight line drawn from head to the tail of turbine blade.

2. Angle between chord and turbine rotation is called as _________

a) blade angle

b) pitch angle

c) relative angle

d) none of the mentioned

Answer: b

Explanation: Angle between the chord and the turbine is called as pitch angle.

3. Angle between steam relative velocity and turbine rotation is called as _________

a) blade angle

b) pitch angle

c) relative angle

d) none of the mentioned

Answer: c

Explanation: Angle between steam relative velocity and turbine rotation is called as relative angle.

4. Relative angle can also be called as ______________

a) incidence angle

b) blade angle

c) pitch angle

d) none of the mentioned

Answer: a

Explanation: Relative angle is the angle at which steam is entering the turbine. It is the angle between relative velocity of steam and turbine. Hence relative angle is also called a incidence angle.

5. Angle between relative velocity of steam and chord is called as _________

a) blade angle

b) pitch angle

c) attack angle

d) relative angle

Answer: c

Explanation: Attack angle is the angle with which steam attacks the blade. Hence it is the angle between relative velocity of steam and chord of the blade.

6. Attack angle is the difference between angle of pitch and relative angle.

a) True

b) False

Answer: a

Explanation: It can be found theoretically by calculating the pitch angle and relative angle. The difference between pitch angle and relative angle is the attack angle.

7. The length of perpendicular line drawn from the highest point of the blade to the chord is called as ______

a) maximum thickness

b) maximum chamber

c) maximum chamber location

d) none of the mentioned

Answer: b

Explanation: Maximum chamber is the length of perpendicular line drawn from the highest point of the blade to the chord.

8. Maximum chamber is represented by ____________

a) m

b) c

c) p

d) none of the mentioned

Answer: a

Explanation: C is used to represent chord and p is used to represent maximum chamber location.

9. Maximum chamber location is represented by _______

a) m

b) c

c) p

d) none of the mentioned

Answer: c

Explanation: Maximum chamber location is represented by p.

10. Chord is represented by __________

a) m

b) c

c) p

d) none of the mentioned

Answer: b

Explanation: Chord is represented by C.

This set of Steam and Gas Turbines Questions and Answers for experienced focuses on “Blade Entrance and Exit Angles, Angle of Efflux”.

1. Angle made by relative velocity vector with horizontal line is called as __________

a) blade entrance angle

b) exit angle

c) entrance angle

d) none of the mentioned

Answer: a

Explanation: Blade entrance angle is the angle with which steam enters the blade. Hence it is the angle made by relative velocity to the horizontal.

2. Blade entrance angle is represented by _________

a) Alpha

b) Theta

c) phi

d) None of the mentioned

Answer: c

Explanation: Blade entrance angle is represented by Phi. Where as Theta is used to represent the Nozzle angle.

3. Angle made by the absolute velocity of steam to the horizontal is called as __________

a) blade entrance angle

b) nozzle angle

c) outlet angle

d) none of the mentioned

Answer: b

Explanation: Nozzle angle is the angle made by the absolute velocity vector with a horizontal line.

4. Nozzle angle is represented by ______

a) Alpha

b) Beta

c) Theta

d) None of the mentioned

Answer: c

Explanation: Nozzle angle is represented by theta.

5. Angle made by the relative velocity vector entering the fixed blades to the horizontal line is called as ____________

a) blade entrance angle

b) blade exit angle

c) nozzle angle

d) none of the mentioned

Answer: b

Explanation: Blade exit angle is the angle made by the relative velocity vector entering the fixed blades to the horizontal line.

6. Blade exit angle is represented by _______

a) Theta

b) Alpha

c) Gamma

d) None of the mentioned

Answer: c

Explanation: Theta is used to represent nozzle angle and gamma is used to represent blade exit angle.

7. Angle made by the absolute velocity vector of steam and blade velocity vector is called as _______

a) nozzle angle

b) exit angle

c) none of the mentioned

d) fluid exit angle

Answer: d

Explanation: Fluid exit angle is the angle made by the absolute velocity vector of fluid and the blade velocity vector.

8. Fluid exit angle is represented by _______

a) Theta

b) Gamma

c) Delta

d) None of the mentioned

Answer: c

Explanation: Theta is used to represent nozzle angle and gamma is used to represent Blade exit angle and Delta is used to represent fluid exit angle.

9. Angle between surface of target and plane perpendicular to the nozzle central line is called as _______

a) blade exit angle

b) reversal efflux angle

c) nozzle angle

d) none of the mentioned

Answer: b

Explanation: Angle between surface of target and plane perpendicular to nozzle central line is called a efflux angle.

10. Angle of vector drawn normal to the exit is called as ______

a) reversal efflux angle

b) nozzle angle

c) blade angle

d) none of the mentioned

Answer: a

Explanation: Angle of vector drawn normal to the exit is called a reversal efflux angle.

This set of Steam and Gas Turbines Multiple Choice Questions & Answers  focuses on “Losses in Impulse Blade Passages”.

1. ____________ is developed when working fluid is passed through blade passage.

a) Internal heat loss

b) External heat loss

c) Heat loss

d) None of the mentioned

Answer: a

Explanation: When working fluid is passing through blade passage, due to friction internal heat loss occurs.

2. Kinetic energy of working fluid is _________ kinetic energy of case lossless flow.

a) Equal to

b) Lesser than

c) Greater than

d) Depends on the situation

Answer: c

Explanation: Kinetic energy of the case lossless flow is lesser than the kinetic energy of working fluid.

3. Ratio of actual velocity to velocity of case lossless flow is called as _______

a) Velocity coefficient

b) Velocity gradient

c) No specific ratio

d) None of the mentioned

Answer: a

Explanation: Velocity coefficient is the ratio of actual velocity to velocity of case lossless flow.

4. Difference between actual enthalpy of working fluid to case enthalpy of isoentropic flow is called as _______

a) Case lossless flow

b) Entropy change

c) Losses

d) None of the mentioned

Answer: c

Explanation: Losses are the enthalpy differences between working fluid and casses of isoentropic flow.

5. The losses occurred due to enthalpy changes is caused due to _________

a) Pressure difference

b) Friction

c) Temperature difference

d) None of the mentioned

Answer: b

Explanation: Friction causes the enthalpy change.

6. Velocity coefficient is applicable for __________

a) Parallel flow passage

b) Counter flow passage

c) All types of flow passages

d) None of the mentioned

Answer: c

Explanation: Velocity coefficient is applicable for all types of flow passages.

7. Velocity coefficient can be applied for ___________ flow passage.

a) convergent

b) divergent

c) depends on

d) none of the mentioned

Answer: a

Explanation: Velocity coefficient can be applied for any flow passage.

8. Velocity coefficient can be applied for __________ blade passage.

a) none

b) impulse

c) reaction

d) any

Answer: d

Explanation: Velocity coefficient can be applied for any flow passage.

9. Blade profile losses for a diffuser blade depends on ____________

a) Enthalpy

b) Entropy

c) Kinetic energy

d) None of the mentioned

Answer: c

Explanation: Blade profile losses for a diffuser blade is related to the kinetic energy.

10. Blade profile losses are ____________ losses of the stages at turbomachine.

a) Greater

b) Smaller

c) Equal

d) None of the mentioned

Answer: b

Explanation: Losses at the stages of turbomachines are greater than blade profile losses.

This set of Steam and Gas Turbines Multiple Choice Questions & Answers  focuses on “Reaction Blade Profiles”.

1. In reaction turbines steam pressure is used in __________ stages.

a) many

b) one

c) two

d) none

Answer: a

Explanation: In reaction turbines turbine rotates due to the reaction of the flow of fluid.

2. In reaction turbine direction of fluid flow is changed drastically.

a) True

b) False

Answer: b

Explanation: In impulse turbine direction of fluid flow is changed drastically where as in reaction turbine the direction is not turned drastically.

3. Steam velocity graph is same for both reaction and impulse turbines.

a) True

b) False

Answer: a

Explanation: Only steam pressure graph differs and steam velocity graph is same for both impulse and reaction turbine.

4. Reaction turbine blades are _________

a) Plate profile type

b) Aerofoil type

c) Circular profile type

d) None of the mentioned

Answer: b

Explanation: Reaction turbine blades are aerofoil type whereas impulse turbine blades are plate profile type.

5. Reaction turbine blades are _____________

a) symmetrical

b) asymmetrical

c) depends on reaction turbine

d) none of the mentioned

Answer: b

Explanation: Reaction turbine blades are asymmetrical.

6. _____________ is run by the impulse of steam.

a) Reaction turbine

b) Reaction & Impulse turbine

c) Impulse turbine

d) None of the mentioned

Answer: c

Explanation: Impulse turbine is run by the impulse of steam.

7. In reaction turbine nozzle directs the ___________ of steam towards the blades.

a) direction

b) rotation

c) direction & rotation

d) none of the mentioned

Answer: b

Explanation: In impulse turbine nozzle directs the direction of steam and whereas in reaction turbine direction of flow directs the rotation of blades.

8. In reaction turbine direction of fluid flow is maintained by _______

a) Nozzles

b) Rotating blades

c) Guide vanes

d) None of the mentioned

Answer: c

Explanation: In reaction turbines the direction of fluid flow is maintained by guide vanes.

9. In reaction turbines fluid ________ while flowing through the passages.

a) expands

b) contracts

c) depends on the flow

d) none of the mentioned

Answer: a

Explanation: In impulse turbines fluid is totally expanded into nozzle and no expansion takes place while flowing through passage whereas in reaction turbine fluid expands during flowing through passage.

10. Different pressures are maintained on ________ sides of reaction turbine blades.

a) one

b) one

c) many

d) none of the mentioned

Answer: d

Explanation: In reaction turbines two different pressure are maintained on two sides as fluid expands during flow.

This set of Steam and Gas Turbines Interview Questions and Answers for experienced focuses on “Blade Angle, Gauging and Pitch, Width and Height”.

1. Ram Air turbine generates ________ from air stream.

a) losses

b) power

c) work

d) none

Answer: b

Explanation: Ram Air turbine generates power from air stream.

2. Ram Air turbine can be connected to hydraulic pump.

a) True

b) False

Answer: a

Explanation: Ram air turbine can be connected to generator or hydraulic pump.

3. In steam and gas turbines Casing contains controls for working fluids.

a) True

b) False

Answer: a

Explanation: In steam and gas turbines casing over turbine blades contains controls for working fluids.

4. When pressure drop is in stages then that turbine is called as ________

a) velocity compounded impulse turbine

b) pressure compounded impulse turbine

c) velocity compounded reaction turbine

d) none of the mentioned

Answer: b

Explanation: In pressure compounded impulse turbine pressure drop is in several stages and pressure loss is reduced.

5. Steam velocities in pressure compounding is ______

a) low

b) high

c) velocity has nothing to do with pressure compounding

d) none of the mentioned

Answer: a

Explanation: In pressure compounding the Conversion of kinetic energy in work is in several small stages and hence velocity of steam is low.

6. In parsons turbine to increase area between blades its height is to be ________

a) height has nothing to do with area between blades

b) decreased

c) increased

d) none of the mentioned

Answer: c

Explanation: In parsons turbine velocity is increased and as a result area between the blades is to be increased and it was increased by tapering the blade height.

7. If specific volume of steam increases its blade height _______

a) increases

b) decreases

c) not related with each other

d) none of the mentioned

Answer: a

Explanation: If the specific volume of steam increases its area need to be increased and hence its blade height is increased.

8. Blade entrance angle is measure for __________

a) stationary blades

b) moving blades

c) stationary & moving blades

d) none of the mentioned

Answer: b

Explanation: Steam initially enters moving blades and hence blade entrance angle is measured for moving blades.

9. Blade exit angle is a measure for _________

a) moving & fixed blade

b) moving blade

c) fixed blade

d) none of the mentioned

Answer: c

Explanation: Steam exits the moving blade and then it enters fixed blade and hence blade exit angle is measured at fixed blades.

10. Nozzle exit angle is the measure of angle with which steam is leaving the nozzle.

a) True

b) False

Answer: a

Explanation: Nozzle exit angle is the angle with which steam exits the nozzle.

This set of Steam and Gas Turbines Multiple Choice Questions & Answers  focuses on “Losses in Reaction Blade Passages”.

1. Passages in steam turbines are _______

a) convergent

b) divergent

c) convergent & divergent

d) none of the mentioned

Answer: a

Explanation: Passages in steam turbines are convergent so that steam expands.

2. The flow of steam through the nozzle is isoentropic.

a) True

b) False

Answer: b

Explanation: The flow of steam is not isoentropic.

3. In reaction turbines a pressure drop occurs between rotors and stator.

a) True

b) False

Answer: a

Explanation: Steam when leaving the stator changes its speed relative to the blade speed and pressure drop occurs.

4. Steam is directed towards rotor by _________

a) rotor vanes

b) moving blades

c) fixed blades

d) none of the mentioned

Answer: c

Explanation: Steam is directed by fixed vanes in steam turbine.

5. Losses that occur when steam is supplied from boiler to turbine is called as ___________

a) regulating loss

b) friction loss

c) gland loss

d) none of the mentioned

Answer: a

Explanation: When steam is supplied from boiler to turbine it passes through regulating valve and some energy loss is occurred while passing through regulating valve which is called as regulating loss.

6. Losses occurred while passing through blades are called as ________

a) efficient losses

b) blade friction loss

c) efficient & blade friction losses

d) none of the mentioned

Answer: b

Explanation: Blade friction loss are caused due to friction between blade and steam and loss occurs due to that friction.

7. Disc friction loss is due to ___________

a) churning action of disc

b) friction between blade and steam

c) pressure drop

d) none of the mentioned

Answer: a

Explanation: Blades re connected to the disc and there will be some amount of energy loss due to churning action of the disc.

8. For fixing blades and rotating components together ___________ are used.

a) bolt and nut

b) valve

c) glands

d) none of the mentioned

Answer: c

Explanation: Glands are used to fix blades and rotating components together.

9. Losses occurred at gap between glands are called as _________

a) valve losses

b) gland losses

c) valve & gland losses

d) none

Answer: b

Explanation: Gland losses are the losses that are occurred at the gap between the glands.

10. Kinetic energy that steam has while coming out of turbines is called as ________

a) residual loss

b) friction loss

c) gland loss

d) none of the mentioned

Answer: a

Explanation: Residual losses are the energy that steam contains while exiting the turbine. This energy cannot be used and hence it is called as residual losses.

This set of Steam and Gas Turbines Multiple Choice Questions & Answers  focuses on “Flow Passages with Radial Equilibrium”.

1. Flow through turbo machinery is ________

a) one dimensional

b) two dimensional

c) three dimensional

d) none of the mentioned

Answer: c

Explanation: Fluid flow in turbo machinery is a three dimensional flow.

2. Third direction of the flow in turbo machinery is _______

a) blade width

b) blade height

c) heat flow direction

d) none of the mentioned

Answer: b

Explanation: Flow direction and tangential flow direction are the two directions and the third direction is blade height.

3. Centrifugal forces acts in ________

a) tangential direction

b) flow direction

c) radial direction

d) none of the mentioned

Answer: c

Explanation: Centrifugal flow acts in the third direction that is radial direction.

4. The field produced by centrifugal force distorts the flow velocity.

a) True

b) False

Answer: a

Explanation: Centrifugal force produced creates a field on the flow and distorts the velocity of flow.

5. Radial equilibrium theory assumes that flow is in equilibrium before and after the fluid entering the blade.

a) True

b) False

Answer: a

Explanation: Radial equilibrium method assumes flow is in equilibrium before the fluid enters and after the fluid leaving the blade.

6. Radial equilibrium theory is more important for Radial flow machines.

a) True

b) False

Answer: b

Explanation: Radial equilibrium theory is more important for axial flow machines.

7. In radial equilibrium method centrifugal force is equated to __________

a) pressure force

b) axial force

c) centripetal force

d) none of the mentioned

Answer: a

Explanation: For a particle to move in constant radius centrifugal force must be equal to pressure force.

8. For radial equilibrium flow radial component must be _______ along the radial direction of flow.

a) higher

b) zero

c) lesser

d) none of the mentioned

Answer: b

Explanation: In radial equilibrium method radial component must be equal to zero.

9. Stagnation enthalpy is _______ in turbo machine along the radial direction.

a) higher

b) zero

c) constant

d) none of the mentioned

Answer: c

Explanation: Stagnation enthalpy is constant in turbo machines along the radial flow direction.

10. Stagnation enthalpy is _________ at intake and discharge.

a) constant

b) low

c) high

d) none of the mentioned

Answer: a

Explanation: Stagnation enthalpy is constant in turbo machines along the radial flow direction at intake and discharge.

This set of Steam and Gas Turbines Multiple Choice Questions & Answers  focuses on “Free and Forced Vortex”.

1. In vortex region flow rotates perpendicular to the axis line.

a) True

b) False

Answer: b

Explanation: In vortex region fluid rotates on an axis line.

2. Viscous friction in the fluid causes the flow to become vortex.

a) True

b) False

Answer: a

Explanation: In the absence of forces viscous friction causes the flow to become vortex.

3. In vortex fluid flow velocity is ______________ to the distance from the axis line.

a) directly proportional

b) inversely proportional

c) not related

d) none of the mentioned

Answer: b

Explanation: In vortex fluid velocity is more near to the axis and decreases as the distance from the axis line increases. Hence Fluid flow velocity is inversely proportional to the distance from the axis line.

4. Vorticity is _______ in the core region.

a) very high

b) very low

c) zero

d) none of the mentioned

Answer: a

Explanation: In the core region fluid rotates with high velocity and hence vorticity is high in the core region.

5. Steam lines and Path lines are _______ in stationary vortex.

a) high

b) less

c) closed

d) none of the mentioned

Answer: c

Explanation: Steam lines and Path lines are closed in stationary vortex where as in moving vortex it carries momentum and energy.

6. In a fluid with constant density Vortex flow pressure is proportional to ________

a) square of the distance from axis

b) distance from the axis

c) cube of the distance from the axis

d) none of the mentioned

Answer: a

Explanation: In a vortex flow with constant fluid density its fluid pressure is inversely proportional to the square of the distance from the axis line.

7. In forced vortex all fluid particles rotate with the ________________

a) constant velocity

b) constant angular velocity

c) variable angular velocity

d) none of the mentioned

Answer: b

Explanation: In forced vortex all fluid vortex rotates with constant angular velocity.

8. Solid body rotation is another name for ________

a) free vortex

b) forced vortex

c) free & forced vortex

d) none of the mentioned

Answer: b

Explanation: Solid body rotation is another name for forced vortex as all fluid particles in forced vortex rotate with same angular velocity like a solid rotation.

9. In forced vortex the total head _______ with radius.

a) radius is not related to head in forced vortex

b) decreases

c) increases

d) none of the mentioned

Answer: c

Explanation: In forced vortex total head increases with radius from the head equation.

10. For forced vortex external torque is to be supplied continuously.

a) True

b) False

Answer: a

Explanation: To maintain forced vortex external energy is to be supplied constantly and hence external torque is to be supplied constantly.

This set of Steam and Gas Turbines Multiple Choice Questions & Answers  focuses on “Control and Perfomance”.

1. Gas turbine controls are classified into ____ types.

a) 1

b) 2

c) 3

d) 4

Answer: b

Explanation: Gas turbine drives are classified into two types.

2. DSC interface is used in __________

a) compressor drive

b) turbine drive

c) compressor & turbine drive

d) none of the mentioned

Answer: c

Explanation: Both DSC interface and Graphic interface is used in both compressor drive and turbine drive.

3. In gas turbines Load control is available in _______

a) compressor drives

b) generator drives

c) compressor & generator drive

d) none of the mentioned

Answer: b

Explanation: Load control is available in generator drives as load can be applied or decreased only on the generator not on the compressor.

4. Communication interfaces are ___________ in steam drives.

a) available

b) not available

c) depends on the usage

d) none

Answer: a

Explanation: Communication interface is available in steam drives.

5. Steam turbine performance is expressed in _______

a) heat rate

b) steam rate

c) heat & steam rate

d) none of the mentioned

Answer: b

Explanation: Steam turbine performance is expressed in steam rate.

6. Gas turbine performance is expressed in terms of _______

a) heat & steam rate

b) steam rate

c) heat rate

d) none of the mentioned

Answer: c

Explanation: Gas turbine performance is expressed in terms of heat rate while steam turbine is expressed in terms of steam rate.

7. Gas turbine performance is directly proportional to the ______

a) inlet air density

b) inlet air temperature

c) inlet air density & inlet air temperature

d) none of the mentioned

Answer: a

Explanation: Gas turbine performance is directly proportional to inlet air density as inlet air density increases its inlet air mass which increases the performance of gas turbine.

8. In a gas turbine power produced is _________ to inlet air density.

a) indirectly proportional

b) directly proportional

c) not proportional

d) one

Answer: b

Explanation: As inlet air density is directly related to the performance of gas turbine, When inlet air density is increased its performance increased which means the power produced by gas turbine is increased.

9. In a gas turbine when firing temperature is __________ engine efficiency changes.

a) increased

b) decreased

c) remained constant

d) none of the mentioned

Answer: a

Explanation: When firing temperature is increased its environmental air conditions are altered so that its engine efficiency changes.

10. In steam turbines vapor and vapor conditions change with time.

a) True

b) False

Answer: a

Explanation: In steam turbine both vapor and vapor conditions are constant and that’s what makes calculating the steam turbine performance easy where as in gas turbines both vapor and vapor conditions are not constant and that makes it difficult for calculating performance.

This set of Steam and Gas Turbines Multiple Choice Questions & Answers  focuses on “Control and Supervisory Instruments”.

1. Radial vibration measurement measures ____________

a) unbalanced masses

b) cracked shafts

c) oil whirl

d) all of the mentioned

Answer: d

Explanation: Radial vibration measurement measures all the unbalanced masses, cracked shafts and also oil whirls.

2. Vibration measurements in steam turbines can be made in _______ planes.

a) 1

b) 2

c) 1 or 2

d) 4

Answer: c

Explanation: Vibration measurements in steam turbines can be measured in single plane or two planes.

3. Absolute shaft measurement is done when __________

a) weight of the rotating assemble is five times more than casing

b) weight of rotating assembly is two time more than the casing

c) weight of the rotating assembly is thrice the casing weight

d) none of the mentioned

Answer: a

Explanation: Absolute shaft measurement measures the shaft motion with respect to the free space. It is done when weight of the shaft assembly is five times more than the weight of casing.

4. Phase measurement is required for accurate balancing of the rotor.

a) True

b) False

Answer: a

Explanation: Phase measurement is required for accurate balancing of any rotor. Because phase is defined as angle between reference mark and heavy spot on the rotor.

5. Eccentricity measurement is used to indicate ______

a) bent shafts

b) when the rotor can be bought to the high speeds

c) bent shafts and when the rotor can be bought to the high speeds

d) none of the mentioned

Answer: c

Explanation: Eccentricity measurement makes us to know about the sag or bow in a rotor which helps us to get knowledge about whether to increase the speed or not.

6. DE measurement is used to get the knowledge about distance between case and rotor.

a) True

b) False

Answer: a

Explanation: As turbine casing has more weight than the rotor, when turbine is under operation it should be taken care that there should not be any contact between turbine and casing due to thermal expansion as turbine has more expansion when compared to the casing.

7. Rotor thrust measurement is done in order to _______

a) monitor thrust

b) monitor bearing wear

c) monitor thrust & bearing wear

d) none of the mentioned

Answer: c

Explanation: Rotor thrust measurement is done in order to monitor thrust and also bears wear.

8. Thrust position measurements are taken within _____ inches of thrust bearing.

a) 10

b) 12

c) 20

d) 24

Answer: b

Explanation: Thrust position measurement is done within 12 inches of thrust bearing.

9. Thrust measurement taken out of 12 inches are effected by ______

a) thrust forces

b) thrust forces & thermal expansions

c) thermal expansions

d) none of the mentioned

Answer: c

Explanation: Measurements taken out of q2 inches are generally effected by thermal expansions.

10. Valve position measurement is used to measure how much valve is used.

a) True

b) False

Answer: a

Explanation: Valve position measurement is used to measure how much the valve is opened, mainly throttle valve which gives us information about how much percentage the load can be increased.

This set of Steam and Gas Turbines Multiple Choice Questions & Answers  focuses on “Direct Speed Responsive Governors”.

1. Governors are used to control speed to ________

a) fuel input ratio

b) fuel input

c) fuel input ratio & fuel input

d) none of the mentioned

Answer: a

Explanation: In governors when speed is increased its throttle increases and more fuel enters which indicates governors are used to control speed to fuel input ratio.

2. Speed/Load control is used to determine the __________ for available load.

a) speed limitation

b) power demand

c) speed limitation & power demand

d) none of the mentioned

Answer: b

Explanation: Speed/Load control is used to determine the fuel demands according to the increase or decrease in load.

3. In aviation jet engine minimum fuel available should be limited during deceleration to avoid ______

a) shut down of the engine

b) combustion blow out

c) to control the load

d) none of the mentioned

Answer: b

Explanation: In aviation jet engine minimum fuel available is limited during deceleration to avoid combustion blow out.

4. In steam turbines governors are used to control __________

a) Isochronic operations

b) Drop operations

c) Isochronic & Drop operations

d) None of the mentioned

Answer: c

Explanation: In general speed responsive governors are used during isochronic and drop operations.

5. The change in fuel flow is called as ________

a) speed error

b) fuel error

c) speed & fuel error

d) none of the mentioned

Answer: a

Explanation: The difference between actual value and the reference value of speed is called an error and change in fuel flow is called as speed error.

6. In drop control __________ is constant.

a) turbine speed

b) reference value

c) turbine speed & reference value

d) none of the mentioned

Answer: b

Explanation: In drop control fuel is controlled by changing the speed error where turbine speed is kept constant by the grid.

7. In drop control fuel flow is directly proportional to _____________

a) turbine speed

b) temperature

c) speed error

d) none of the mentioned

Answer: c

Explanation: In drop control the turbine speed is maintained constant and fuel flow is directly proportional to speed error, so to change the fuel flow reference value is either increased or decreased.

8. In drop control if the turbine speed was not constant at the grid then speed would __________

a) raise

b) drop

c) remains constant

d) none of the mentioned

Answer: b

Explanation: In drop control turbine speed is remained constant and speed error is varied by changing reference value.

9. In drop governor at 100% turbine speed the output is __________

a) 50%

b) 40%

c) 60%

d) 70%

Answer: a

Explanation: To obtain 50% output the speed should be 100%. This can be obtained from graph.

10. When set point is increased to 103% the output is __________

a) 60%

b) 50%

c) 75%

d) 45%

Answer: c

Explanation: From graph it can be obtained that when set point is 103% its output is 75%.

This set of Steam and Gas Turbines Multiple Choice Questions & Answers  focuses on “Hydraulic Speed Responsive Governor”.

1. _____________ is the standard hydraulic governor used in prime movers.

a) Dash type isochronous governor

b) Drop governor

c) Dash type isochronous & Drop governor

d) None of the mentioned

Answer: a

Explanation: Dash type isochronous governor is the standard hydraulic governor used in prime movers.

2. Dash type isochronous governor gives _________________ control.

a) Proportional

b) Integrational

c) Proportional & Integrational

d) None of the mentioned

Answer: c

Explanation: Dash type isochronous governor gives both proportional and integral control.

3. Hydraulic governors have ________ adjustability to control.

a) rich

b) poor

c) medium

d) none of the mentioned

Answer: b

Explanation: Hydraulic governors have poor adjustability to control and that is a major disadvantage.

4. In hydraulic governors load control is given by servo motors.

a) True

b) False

Answer: b

Explanation: In some hydraulic governors load control is given by servo motors but not in all the hydraulic governors.

5. Mechanical governors have __________ moving parts than hydraulic governors.

a) less

b) more

c) equal

d) none of the mentioned

Answer: a

Explanation: Hydraulic governors have more moving parts than mechanical governors.

6. Hydraulic governors are ________ sensitive when compared to mechanical governors.

a) less

b) more

c) equal

d) none of the mentioned

Answer: b

Explanation: Hydraulic governors are more sensitive than mechanical governors.

7. In hydraulic governors power that moves engine throttle comes from the speeding device.

a) True

b) False

Answer: b

Explanation: In hydraulic governor power that moves the engine throttle comes from the piston.

8. In hydraulic governors speed measuring device is connected to ________

a) Piston

b) Power shaft

c) Pilot valve

d) None of the mentioned

Answer: c

Explanation: The speed measuring device is connected to a pilot valve in hydraulic governors.

9. _____________ is connected to servomotor in hydraulic governor.

a) Pilot valve

b) Pressure valve

c) Pilot & Pressure valve

d) None of the mentioned

Answer: a

Explanation: Pilot valve has bush that moves up and down having ports that control servomotor.

10. For sliding of pilot valve it requires ______ force and it is generated from piston.

a) large

b) small

c) medium

d) none of the mentioned

Answer: b

Explanation: Small amount of force is required to slide the pilot valve.

This set of Steam and Gas Turbines Multiple Choice Questions & Answers  focuses on “Pressure Regulators”.

1. Gas pressure regulators are also used to measure flow rates.

a) True

b) False

Answer: b

Explanation: Gas pressure regulators are used to regulate gas pressure and not to measure flow rates. Flow meter, rotameter, etc are used to measure the flow rates.

2. In pressure regulators load flow is ___________ proportional to regulator flow.

a) directly

b) indirectly

c) depends

d) none

Answer: a

Explanation: In pressure regulators if load flow increases regulator flow should also increase i.e load flow is directly proportional to regulator flow.

3. A pressure regulator consists of __________

a) Restricting element

b) Loading element

c) Measuring element

d) All of the mentioned

Answer: d

Explanation: Pressure regulator consists of a restricting element, a loading element, and a measuring element.

4. Restricting element in a pressure regulator can be _________

a) Globe valve

b) Poppet valve

c) Butterfly valve

d) All of the mentioned

Answer: d

Explanation: Restricting the element of a pressure regulator is a valve. It can be a globe valve or poppet valve or butterfly valve.

5. Diaphragm actuator can be used as loading element.

a) True

b) False

Answer: a

Explanation: Loading element is something that bears force. Diaphragm actuator can also be used as loading element.

6. Loading element in the pressure regulator can be ______

a) Spring

b) Weight

c) Piston actuator

d) All of the mentioned

Answer: d

Explanation: Loading element is something that provides necessary force to the restricting element.

7. The measuring element _______________

a) Measures the inlet flow

b) Measures the outlet flow

c) Compares the inlet flow to the outlet flow

d) None of the mentioned

Answer: c

Explanation: Measuring element is used to determine when the inlet flow is equal to outlet flow.

8. Diaphragm can be used as ___________

a) measuring element

b) combining element

c) measuring & combining element

d) none of the mentioned

Answer: d

Explanation: Diaphragm can also be used as measuring element. It can be used as combined element.

9. Pressure regulators can be used in _______

a) Air compressors

b) Aircraft

c) Aerospace

d) All of the mentioned

Answer: d

Explanation: Pressure regulators are used where the pressure needs to be regulated according to the inlet flow.

10. _____________ are used in gas powered vehicles.

a) pressure regulators

b) temperature regulators

c) pressure & temperature regulators

d) none of the mentioned

Answer: a

Explanation: Pressure regulators are used in gas powered vehicles as the stored gas is needed to bring to the operating pressure from a high pressure of about 700 bar.

This set of Steam and Gas Turbines Multiple Choice Questions & Answers  focuses on “Speed Regulation and Parallel Operation”.

1. ___________ variations can also be used in speed regulation of gas turbines.

a) Pressure

b) Fuel flow

c) Temperature

d) None of the mentioned

Answer: b

Explanation: Fuel flow variations can be used in speed regulations in gas turbines.

2. Nozzle area variations are used in speed regulations in gas turbines.

a) True

b) False

Answer: a

Explanation: Fuel flow variations and nozzle area variations can be used in speed regulations in gas turbines.

3. If the electrical load is greater than the speed then _________

a) Turbine shuts down

b) Speed decreases

c) Speed increases

d) None of the mentioned

Answer: b

Explanation: When electrical load increases than the generation then turbine speed decreases.

4. When gas turbines are operated in parallel their disturbances ________

a) Increases

b) Decreases

c) Does not change

d) None of the mentioned

Answer: a

Explanation: When gas turbines are parallelly operated their disturbances increases.

5. In parallel operation speed governor is connected to ______________

a) digital set point

b) fuel system

c) actual speed

d) none of the mentioned

Answer: b

Explanation: In parallel operation speed governor is connected to fuel system.

6. Microprocessor based synchronizer operates on set point.

a) True

b) False

Answer: b

Explanation: Conventional synchronizing relay operates on set point.

7. Synchronizing relay has a time period of ___________

a) 5 minutes

b) 3 minutes

c) 6 minutes

d) 8 minutes

Answer: c

Explanation: Synchronizing relay has a time period of 6 minutes.

8. Microprocessor based synchronizer has a time period of _______

a) 4.5 minutes

b) 5 minutes

c) 8 minutes

d) 6 minutes

Answer: a

Explanation: Microprocessor synchronizer is an advanced synchronizer and has lesser time than synchronizing relay.

9. Inputs given to speed governor are __________

a) Digital set point

b) Actual speed

c) Digital set point & Actual speed

d) None of the mentioned

Answer: c

Explanation: Digital set point and actual speed are the inputs given to the speed governor.

10. PID controller is used to make the offset ________

a) Zero

b) Positive

c) Negative

d) None of the mentioned

Answer: a

Explanation: PID controller is used to make the offset zero.

This set of Steam and Gas Turbines Multiple Choice Questions & Answers  focuses on “Emergency Governors”.

1. Only some special steam turbines used for special purposes are provided with emergency governors.

a) True

b) False

Answer: b

Explanation: Every steam turbine is provided with an emergency governor.

2. When the speed of the shaft is increased by ________ emergency governors starts.

a) 95%

b) 110%

c) 100%

d) 90%

Answer: b

Explanation: When the speed of the governor is 110% then emergency governors starts working.

3. When balancing of turbine is disturbed _______________

a) Emergency governor starts

b) Governor shuts down

c) Emergency governor starts & Governor shuts down

d) None of the mentioned

Answer: a

Explanation: When balancing of turbines is disturbed, emergency governor starts working.

4. When lubrication system fails _______

a) Turbine shuts down

b) Emergency governor starts

c) Turbine shuts down & Emergency governor starts

d) None of the mentioned

Answer: b

Explanation: When lubrication system fails emergency governor fails.

5. Emergency governor starts working when condenser vacuum is ___________

a) less

b) more

c) medium

d) none of the mentioned

Answer: a

Explanation: When turbine vacuum is reduced emergency governor starts working.

6. When coolant supply is inadequate to condenser ____________

a) Emergency governor starts

b) Condenser instantly shuts down

c) Emergency governor starts & Condenser instantly shuts down

d) None of the mentioned

Answer: a

Explanation: When coolant supply to condenser is inadequate emergency governor starts.

7. Emergency governor starts when _____________

a) Lubrication system fails

b) Turbine balance is disturbed

c) Speed is increased to 110%

d) All of the mentioned

Answer: d

Explanation: Emergency governor starts when

Lubrication system fails

Turbine balancing is disturbed

Speed is increased to 110%.

8. How many governors are required for safe operation of the turbine?

a) 2

b) 1

c) 3

d) 4

Answer: a

Explanation: Two independent governors are required for safe operation. They are

Main governor

Emergency governor.

9. Speed regulation varies from ____________

a) 2.5%-5%

b) 3%-5%

c) 1%-5%

d) 1%-2%

Answer: a

Explanation: Speed regulation varies from 2.5%-5%.

10. Overspeed test for turbine can be done by ____ methods.

a) 1

b) 2

c) 3

d) 4

Answer: b

Explanation: Overspeed test can be done by two methods. They are

DEH dielectric test

Mechanical Test.

This set of Steam and Gas Turbines Multiple Choice Questions & Answers  focuses on “Turbine Perfomance and Effect of Throttle Governing”.

1. In small turbines initial cost for throttle governing is ________

a) Low

b) High

c) Same as of Big turbines

d) None of the mentioned

Answer: a

Explanation: In small turbines initial cost of throttle governing is low.

2. In small turbines throttle valve is actuated by ________

a) Pneumatic governor

b) Hydraulic governor

c) Centrifugal governor

d) None of the mentioned

Answer: c

Explanation: In small turbines throttle valve is actuated by centrifugal governor.

3. Turbine shaft and rotating shafts are connected by a gear mechanism.

a) True

b) False

Answer: a

Explanation: Both turbine shaft and rotating shaft are connected by a gear mechanism.

4. Sleeves of the governor rotate ___________

a) perpendicularly

b) parallel

c) axially

d) none of the mentioned

Answer: c

Explanation: Both turbine shaft and rotating shafts are connected by a gear mechanism axially.

5. When the load is decreased the turbine shaft speed is ____________

a) decreased

b) increased

c) remains constant

d) none of the mentioned

Answer: b

Explanation: When the load is decreased the turbine shaft speed is increased.

6. In big turbines ________ is used to increase the lever sensitivity.

a) Servo mechanism

b) Centrifugal governor

c) Gear mechanism

d) None of the mentioned

Answer: a

Explanation: In big turbines servo mechanism is used to increase the lever sensitivity.

7. Small deflections in the lever are magnified by _______

a) mass flow Governor

b) servo mechanism

c) mass flow

d) none of the mentioned

Answer: c

Explanation: Small deflections in the lever are magnified by relay system.

8. When volume of flow is limited produced power _______

a) Limits

b) Varies

c) There is no relation

d) None of the mentioned

Answer: a

Explanation: When volume of flow is limited it limits produced power also.

9. Pressure of the steam is __________ at the entry during throttle governing.

a) increased

b) decreased

c) remained constant

d) none of the mentioned

Answer: b

Explanation: In throttle governing available energy is limited by reducing the pressure of steam at the entry.

10. In throttle governing, flow rate is controlled by steam control valve.

a) True

b) False

Answer: a

Explanation: Partially opened steam controlled valve is used to control flow rate in throttle governing.

This set of Steam Turbines Questions for campus interviews focuses on “Effect of Initial Pressure and Temperature Changes”.

1. When initial pressure of the steam turbine is not upto the designed pressure then power produced will _________

a) Increase

b) Decrease

c) Remains constant

d) None of the mentioned

Answer: b

Explanation: When initial pressure of the steam turbine is less than the designed pressure it power production is reduced.

2. When initial temperature of the steam turbine is not upto the designed conditions then power production is ________

a) Reduced

b) Increased

c) Remains constant

d) None of the mentioned

Answer: a

Explanation: When initial temperature of the steam turbine is less than the designed temperature its power production is reduced.

3. In gas turbines change in temperature does affect _________

a) pressure

b) mass flow

c) temperature

d) none of the mentioned

Answer: b

Explanation: In gas turbines change in temperature affect mass flow.

4. In gas turbines change in the humidity affects the _________

a) pressure

b) mass flow

c) temperature

d) none of the mentioned

Answer: b

Explanation: In gas turbines change in humidity affects mass flow.

5. In gas turbines mass flow is related to _________

a) pressure

b) temperature

c) pressure & temperature

d) none of the mentioned

Answer: a

Explanation: In gas turbines mass flow depends on pressure when pressure changes mass flow also changes.

6. Power produced depends on the _________ in gas turbines.

a) volume

b) mass flow

c) volume & mass flow

d) none of the mentioned

Answer: b

Explanation: As gas turbines works on brayton cycle when mass flow changes the net power produced also changes.

7. ___________ also plays a major role in gas turbine performance.

a) Inlet air density

b) Inlet air humidity

c) Inlet air density & humidity

d) None of the mentioned

Answer: a

Explanation: Gas turbine performance depends on inlet air density and environmental conditions.

8. Anything that changes density __________ gas turbine performance.

a) can not effect

b) can effect

c) depends

d) none of the mentioned

Answer: b

Explanation: When density is changed its mass flow rates is changed and that’s how gas turbine performance is changed.

9. The air density is a function of ambient temperature.

a) True

b) False

Answer: a

Explanation: When density is increased its volume is decreased and then its temperature also decreases when pressure is constant. So air density is a function of ambient temperature.

Answer: d

Explanation: Air density is the function of humidity, ambient temperature and pressure.

This set of Steam and Gas Turbines Multiple Choice Questions & Answers  focuses on “Effect of Nozzle Governing”.

1. In nozzle governing flow rate is controlled by only ______________

a) closing nozzle

b) opening nozzle

c) closing & opening nozzle

d) none of the mentioned

Answer: b

Explanation: In nozzle governing flow rate is controlled by either opening or closing the valves.

2. ________ is regulated in nozzle governing.

a) Pressure

b) Temperature

c) Flow rate

d) None of the mentioned

Answer: c

Explanation: In nozzle governing flow rate is controlled by opening or closing the valves instead of regulating the pressure.

3. In nozzle governing Every nozzle is controlled by a separate valve.

a) True

b) False

Answer: a

Explanation: In nozzle governing each nozzle is controlled by a separate valve.

4. In turbine nozzle governing is applied on _________

a) 2nd stage

b) 1st stage

c) Final stages

d) 3rd stage

Answer: b

Explanation: In turbine nozzle governing is applied in first stage and remaining stages will be un affected.

5. Remaining stages of the turbine other than first stage remains ____________ in nozzle governing.

a) unaffected

b) affected

c) unaffected & affected

d) none of the mentioned

Answer: a

Explanation: Nozzle governing is applied only in first stage and remaining stages are unaffected as no pressure regulation is applied.

6. ________ boiler pressure can be obtained from nozzle governing.

a) Depends on the load

b) Partial

c) Full

d) None of the mentioned

Answer: c

Explanation: Full boiler pressure can be obtained as no pressure regulation is done.

7. _________ boiler temperature can be utilized by this nozzle governing.

a) Full

b) Partial

c) Depends on the load

d) None of the mentioned

Answer: a

Explanation: As there is no pressure regulation temperature also does not change and hence full boiler temperature can be used.

8. In subsequent stages of turbine pressure regulation is done.

a) True

b) False

Answer: b

Explanation: In subsequent stages of turbine pressure regulation is not done.

9. In nozzle when entropy ___________ supersaturation occurs.

a) increases

b) decreases

c) remains constant

d) none of the mentioned

Answer: a

Explanation: In nozzle supersaturation causes an increase in entropy.

10. When mass flow rate is maximum nozzle chokes.

a) True

b) False

Answer: a

Explanation: Nozzle chokes when mass flow rate is maximum during critical conditions.

This set of Steam and Gas Turbines Multiple Choice Questions & Answers  focuses on “Parsons Number and Quality Factor”.

1. Vapor quality is the ___________ stored in the steam.

a) mass factor

b) pressure factor

c) temperature factor

d) none of the mentioned

Answer: a

Explanation: Vapor quality is used to know the amount of mass stored in steam.

2. Saturated liquid’s vapor quality is ________

a) 100%

b) 50%

c) 0%

d) 60%

Answer: c

Explanation: In a saturated liquid no vapor is present and hence vapor quality of saturated liquid is 0%.

3. Vapor quality of saturated steam is ________

a) 100%

b) 50%

c) 0%

d) 60%

Answer: a

Explanation: In a saturated vapor the vapor quality is 100%.

4. Vapor quality is an ___________

a) extensive property

b) intensive property

c) extensive & intensive property

d) none of the mentioned

Answer: b

Explanation: Vapor quality is an intensive property.

5. Vapor quality cannot be used to distinguish thermodynamic state of the fluid from others.

a) True

b) False

Answer: b

Explanation: As vapor quality is an intensive property it can be used with the other intensive properties to distinguish the thermodynamic stage.

6. Vapor quality can be calculated by ____________ the total mass of the vapour present with mass of the fluid.

a) dividing

b) multiplying

c) adding

d) none of the mentioned

Answer: a

Explanation: Vapor quality is obtained by dividing mass of the vapor present in fluid with the total mass of the fluid.

7. ________ quality steam contains low moisture percentage.

a) high

b) medium

c) low

d) none of the mentioned

Answer: c

Explanation: Low quality steam has high moisture percentage.

8. ________ quality steam causes corrosion.

a) high

b) low

c) medium

d) none of the mentioned

Answer: b

Explanation: As low quality steam contains high moisture percentage, it corrodes easily.

9. In steam whistles steam quality determines the ___________

a) velocity of sound

b) pressure

c) temperature

d) none of the mentioned

Answer: a

Explanation: Velocity of sound in steam whistles depends on steam quality as steam inertia depends on steam quality.

10. Specific volume of steam is ___________ to dryness faction at given temperature.

a) not related

b) indirectly proportional

c) directly proportional

d) none of the mentioned

Answer: c

Explanation: At given temperature specific volume of steam increases with an increase in dryness faction.

This set of Steam and Gas Turbines Multiple Choice Questions & Answers  focuses on “Automatic Extraction Turbines”.

1. Extraction turbines has an opening in its casing.

a) True

b) False

Answer: a

Explanation: Extraction steam turbines has an opening in its casing.

2. __________ steam is moved to condenser from the turbine in a single step.

a) Total

b) partial

c) depends on load

d) none of the mentioned

Answer: b

Explanation: Some of the steam is extracted at intermediate pressure from casing and the remaining steam is sent to condenser.

3. The steam extraction is __________ extracted.

a) automatically

b) manually

c) automatically or manually

d) none of the mentioned

Answer: c

Explanation: The steam extraction may or may not be automatically extracted.

4. Regulated extraction _________ the total electricity produced.

a) reduces

b) increases

c) has no effect on

d) none of the mentioned

Answer: b

Explanation: Regulated extraction increases the additional electricity produced by steam extraction from casing.

5. Each extracting points on the casing has ______ temperature.

a) different

b) same

c) depends on the load

d) none of the mentioned

Answer: a

Explanation: At each extracting point there will be a different pressure and hence temperature also changes.

6. Each extracting points on the casing has _______ pressure.

a) same

b) different

c) depends on the load

d) none of the mentioned

Answer: b

Explanation: Each extracting point on the casing has a different temperature and pressure.

7. Automatic extraction turbines generate electrical energy.

a) True

b) False

Answer: a

Explanation: Automatic extraction turbines generate both electrical and thermal energy.

8. Automatic extraction turbine generate __________

a) mechanical & thermal energy

b) mechanical energy

c) thermal energy

d) none of the mentioned

Answer: c

Explanation: Automatic extraction turbine generate both electrical and thermal energy.

9. __________ extraction turbines are combined heat and power supply turbines.

a) Automatic

b) Manual

c) Manual or Automatic

d) None of the mentioned

Answer: a

Explanation: Combined heat and power supply turbines are classified as automatic extraction turbines,back pressure turbines and back pressure extraction turbines.

10. In automatic extraction turbines pressure of extracted steam is maintained by __________

a) Extraction points on case

b) Control system

c) Extraction points on case and Control system

d) None of the mentioned

Answer: b

Explanation: In automatic extraction turbines pressure of extracted steam is maintained by control system.

This set of Steam and Gas Turbines Multiple Choice Questions & Answers  focuses on “Mixed Pressure Turbine Perfomance”.

1. Mixed pressure steam turbines are driven by _________ kinds of steam.

a) 1

b) 2 or more

c) 3

d) 5

Answer: b

Explanation: Mixed pressure turbines are driven by two or more kinds of steam.

2. In mixed pressure turbine existing boiler can be combined with new boiler.

a) True

b) False

Answer: a

Explanation: Both the steams are fed into turbine independently and in this type of turbine existing boiler can be combined with new boiler.

3. In dual heat sources optimum heat for each condition cannot be selected in mixed pressure turbine.

a) True

b) False

Answer: b

Explanation: In dual heat sources optimum heat for each condition can be selected in mixed pressure turbine.

4. Radial turbines gain their high efficiencies at the speed ratio of ___________

a) 0.5

b) 0.7

c) 1

d) 2.6

Answer: c

Explanation: Radial turbines get their peak efficiencies at the speed ratio of 0.7

5. Radial turbine has _______ degree of freedom when compared to mixed flow turbine.

a) more

b) less

c) equal

d) none of the mentioned

Answer: b

Explanation: Radial turbine has less degree of freedom when compared to mixed flow turbine.

6. The blade inlet angle at radial blade section is ________ in mixed flow turbine.

a) non zero

b) zero

c) depends on the mass flow rate

d) none of the mentioned

Answer: a

Explanation: The blade inlet angle at radial blade section is non zero in mixed flow turbine.

7. Stress levels in mixed flow turbine are ________

a) high

b) less

c) medium

d) none of the mentioned

Answer: b

Explanation: Stress levels in mixed flow turbines are less.

8. Mixed flow turbines are designed at ________ inertia.

a) high

b) medium

c) low

d) none of the mentioned

Answer: c

Explanation: Mixed flow turbines are designed at low inertia.

9. Radial turbines are characterized by ____________

a) radial fibers

b) centrifugal compressors

c) radial compressors

d) none of the mentioned

Answer: a

Explanation: Radial turbines are characterized by radial fibers.

10. Turbochargers in automobiles works under _______ pulsation inlet flows.

a) low

b) high

c) medium

d) none of the mentioned

Answer: b

Explanation: Turbochargers in automobiles works under high pulsation inlet flows.

This set of Steam and Gas Turbines Multiple Choice Questions & Answers  focuses on “AIEE-ASME Preferred Standard Turbine”.

1. AIEE ASME preferred turbines don’t have any side condensers.

a) True

b) False

Answer: b

Explanation: AIEE ASME preferred turbine have side condensers mounted.

2. Usage of condensers mounted on sides reduces the ___________

a) Power supply

b) Support structures

c) Temperature

d) None of the mentioned

Answer: b

Explanation: Usage of condensers mounted on sides reduces the height of the turbine and support structures can be reduced.

3. AIEE ASME preferred standard power plant is first operated in Greens Bayou electric power plant.

a) True

b) False

Answer: a

Explanation: AIEE ASME preferred standard power plant was first operated in greens bayou electric power plant.

4. The capacity of first AIEE ASME preferred standard turbine is _______

a) 105MW

b) 55MW

c) 66MW

d) 77MW

Answer: c

Explanation: The capacity of AIEE ASME preferred standard turbine generator which first came into use is 66MW.

5. AIEE-ASME preferred standard turbine was presented in _______ ratings when first came into outdoor use.

a) 2

b) 8

c) 3

d) 6

Answer: b

Explanation: AIEE-ASME preferred standard turbine was presented in 8 ratings when it first came into existence. They are 12.65 MW, 16.5 MW, 22 MW, 33 MW, 44 MW, 66 MW, 100 MW, 150 MW.

6. Gantry rolling over the turbine deck ________ on AIEE-ASME preferred standard turbine.

a) done

b) not done

c) depends on the use

d) none of the mentioned

Answer: a

Explanation: Gantry rolling over the turbine deck can be done on AIEE-ASME preferred standard turbine.

7. Outdoor lagging of the turbine generator _________ the effectiveness of the time.

a) reduces

b) increases

c) depends on the load

d) none of the mentioned

Answer: b

Explanation: Outdoor lagging of the turbine generator increases the effectiveness of the time.

8. The outdoor lagging for AIEE-ASME preferred standard turbine is designed for ________

a) 70 P/Sq.ft

b) 80 P/Sq.ft

c) 90 P/Sq.ft

d) 85 P/Sq.ft

Answer: a

Explanation: Outdoor lagging of AIEE-ASME preferred standard turbine is designed for 70 P/Sq.ft.

9. Green Bayou Turbine generator rotates at __________

a) 4000rpm

b) 3000 rpm

c) 3600 rpm

d) 3100 rpm

Answer: c

Explanation: Green Bayou turbine generator works at 3600 rpm.

10. Power factor of Green bayou turbine generator is ______

a) 85

b) 95

c) 60

d) 70

Answer: a

Explanation: Green bayou has a power factor of 85.

This set of Steam and Gas Turbines Multiple Choice Questions & Answers  focuses on “Centrifugal Compressor”.

1. Centrifugal compressors are also known as ____________

a) turbo compressors

b) radial compressors

c) turbo & radial compressors

d) none of the mentioned

Answer: b

Explanation: Centrifugal compressors sometimes called as radial compressors.

2. In idealized turbo machinery, pressure rise is done by adding _______

a) Temperature

b) Mass

c) Kinetic energy

d) None of the mentioned

Answer: c

Explanation: In idealized turbo machinery the pressure rise is done by adding kinetic energy.

3. The pressure rise in impeller is _________ the rise in diffuser.

a) equal to

b) greater than

c) equal to or greater than

d) none of the mentioned

Answer: d

Explanation: Not in all cases pressure rise in diffuser equals to pressure rise in impeller in some cases pressure rise in impeller will be more than that of diffuser.

4. In centrifugal compressor velocity of flow leaving the impeller is equals to _______ in many cases.

a) Speed of sound

b) Double the speed of sound

c) Triple the speed of sound

d) None of the mentioned

Answer: a

Explanation: Initially the flow enters straightly into the impeller and the impeller pushes the flow inwards to spin faster and finally when the flow is leaving impeller it has almost speed of sound.

5. ________ are used as stationary compressors in steam turbines.

a) Moving vanes

b) Guide vanes

c) Moving & Guide vanes

d) None of the mentioned

Answer: b

Explanation: Guide vanes are used as stationary compressors where guide vanes reduce the velocity and according to Bernoulli’s theorem when velocity is reduced its pressure is increased.

6. ________________ has large change in inlet to exit radius when compared to centrifugal compressors.

a) Axial compressors

b) Axial & Centrifugal compressors

c) Centrifugal compressors

d) None of the mentioned

Answer: c

Explanation: Centrifugal compressors has large change in inlet to exit temperature when compared to axial compressor.

7. The first part in both centrifugal compressor and axial compressor are similar.

a) True

b) False

Answer: a

Explanation: The first in both centrifugal compressor and axial compressor are similar.

8. Centrifugal compressor __________ the energy by increasing the radius where as centrifugal fan decreases the energy.

a) increases

b) decreases

c) both follow the same

d) none of the mentioned

Answer: b

Explanation: Both centrifugal compressor and centrifugal fan are similar as both increases the energy by reducing the radius.

9. Centrifugal compressors increases the density of fluid more than ________

a) 1%

b) 3%

c) 5%

d) 7%

Answer: c

Explanation: Centrifugal compressors increases the density of fluid more than 5 %.

10. Centrifugal fan has relative fluid velocities ______

a) Mach number more than 0.3

b) Mach number less than 0.1

c) Mach number less than 0.3

d) Mach number more than 0.5

Answer: c

Explanation: Centrifugal fans often operate at fluid velocities less than mach number 0.3.

This set of Steam and Gas Turbines Multiple Choice Questions & Answers  focuses on “Energy Transfer Relation and Losses”.

1. Temperature of the steam leaving the boiler is ____________

a) low

b) high

c) medium

d) none of the mentioned

Answer: b

Explanation: Steam leaves the boiler at super heated stage with high temperature.

2. Pressure of the steam leaving the boiler is ______

a) low

b) medium

c) high

d) none of the mentioned

Answer: c

Explanation: Steam leaves the boiler at super heated stage with high pressure.

3. Steam when passes through the nozzle _______ its kinetic energy.

a) Increases

b) Decreases

c) Nozzle has nothing to do with kinetic energy

d) None of the mentioned

Answer: a

Explanation: When steam is passed through the nozzle its velocity increases as a result its kinetic energy increases.

4. In a reaction turbine fixed nozzle is replaced by __________

a) guide blades

b) fixed blades

c) moving vanes

d) none of the mentioned

Answer: b

Explanation: In a reaction turbine the work of increasing kinetic energy is done by fixed blades.

5. Work done by the condenser is product of mass flow and _______

a) final enthalpy

b) initial enthalpy

c) change in enthalpy

d) none of the mentioned

Answer: c

Explanation: Work done by the condenser is product of mass flow and change in enthalpy.

6. Turbine performance is ____________ proportional to isoentropic efficiency.

a) directly

b) inversly

c) not proportional

d) none of the mentioned

Answer: a

Explanation: Turbine performance is directly proportional to isoentropic efficiency.

7. While calculating isoentropic efficiency heat loss to the surroundings is assumed to be _______

a) high

b) low

c) medium

d) none of the mentioned

Answer: b

Explanation: While calculating isoentropic efficiency heat loss to the surrounding is assumed to be zero.

8. The starting temperature of actual turbine is ________ the ideal turbine.

a) less than

b) greater than

c) equal to

d) none of the mentioned

Answer: c

Explanation: The starting temperature of the both actual and ideal turbine is equal.

9. The starting pressure of actual turbine is __________ that of ideal turbine.

a) equal to

b) more than

c) less than

d) none of the mentioned

Answer:a

Explanation: The starting pressure of both actual and ideal turbine is equal.

10. Isoentropic efficiency is the _________ of actual work and ideal work.

a) product

b) ratio

c) sum

d) none of the mentioned

Answer: b

Explanation: Isoentropic efficiency is the ratio of actual work to ideal work.

This set of Steam Turbines Aptitude Test focuses on “Adiabatic Efficiency “.

1. Adiabatic efficiency is the ___________ of actual work required by condenser to bring to certain temperature and actual work input.

a) product

b) ratio

c) sum

d) none of the mentioned

Answer: b

Explanation: Adiabatic efficiency is the ratio of work required to raise to a certain temperature to actual work input.

2. While calculating adiabatic efficiency of a nozzle exit conditions for iso-entropic nozzle are ___________

a) Exit temperature are equal

b) Exit pressure’s are equal

c) Inlet states are same

d) All of the mentioned

Answer: d

Explanation: While calculating adiabatic efficiency of nozzle exit temperature, pressure and inlet states of iso-entropic nozzle are treated the same as normal one.

3. For calculating adiabatic efficiency they are ________ iso-entropic efficiency.

a) not compared with

b) compared with

c) multiplied with

d) none of the mentioned

Answer: b

Explanation: Adiabatic efficiency is always calculated by comparing with isoentropic efficiency.

4. It is assumed that all the processes internally are _________

a) reversible

b) irreversible

c) reversible but not in all conditions

d) none of the mentioned

Answer: a

Explanation: It is assumed that all the processes internally are reversible.

5. In air standard assumption combustion is replaced by ___________

a) heat rejection

b) heat addition

c) compression

d) none of the mentioned

Answer: b

Explanation: In air standard assumption combustion is replaced by heat addition.

6. In air standard assumptions heat exhaust process is replaced by _________

a) heat addition

b) compressio

c) heat rejection

d) none of the mentioned

Answer: c

Explanation: In air standard assumptions exhaust process is replaced by heat rejection process.

7. In air standard process working fluid air is assumed as an ____________

a) ideal gas

b) inert gas

c) high pressure gas

d) none of the mentioned

Answer: a

Explanation: In air standard assumptions working fluid air is assumed as ideal gas and assumed to rotate in closed loop.

8. In Air standard cycle air standard assumptions are ________

a) not applicable

b) applicable

c) depends on the situation

d) none of the mentioned

Answer: b

Explanation: Air standard cycle is a cycle where air standard assumptions are applicable.

9. Maximum work output that can be obtained from a system is called as _______

a) Adiabatic efficiency

b) Isoentropic efficiency

c) Availability

d) None of the mentioned

Answer: c

Explanation: Availability is the maximum work output that can be obtained from a system.

10. Combination of _______ vapor cycles is called as binary vapor cycle.

a) two

b) one

c) multi

d) none of the mentioned

Answer: a

Explanation: Binary vapor cycle is a combination of two cycles one operated at high temperatures and others operated at low temperatures.

This set of Steam and Gas Turbines Multiple Choice Questions & Answers  focuses on “Effect of Compressibility”.

1. When mach number is less than 1 flow is __________

a) Subsonic flow

b) Transonic flow

c) Supersonic flow

d) None of the mentioned

Answer: a

Explanation: For subsonic flow mach number is always less than one.

2. When mach number is equal to one then the flow is ___________

a) Subsonic flow

b) Transonic flow

c) Supersonic flow

d) None of the mentioned

Answer: b

Explanation: For transonic flow mach number is equal to one.

3. When mach number is greater than one flow is ___________

a) Subsonic flow

b) Transonic flow

c) Supersonic flow

d) None of the mentioned

Answer: c

Explanation: For supersonic flow mach number is always greater than one.

4. For subsonic flow density varies relatively.

a) True

b) False

Answer: b

Explanation: For subsonic flow density is relatively constant.

5. For transonic flow density change is ________ velocity change.

a) equal to

b) more than

c) less than

d) none of the mentioned

Answer: a

Explanation: For transonic flow density change is almost equal to velocity change.

6. For supersonic flow density changes ___________ velocity change.

a) faster than

b) slower than

c) equal to

d) none of the mentioned

Answer: a

Explanation: For supersonic flow density change is faster than velocity change.

7. In a supersonic flow density change is faster than velocity change by a factor of _________

a) Mach number

b) Square of mach number

c) Cube of mach number

d) None of the mentioned

Answer: b

Explanation: In supersonic flow density change is greater than velocity change by a factor of square of mach number.

8. For compressible flow mach number must be ____________ 0.3.

a) less than

b) equal to

c) greater than

d) none of the mentioned

Answer: c

Explanation: For compressible flow mach number should be greater than 0.3.

9. When normal shock waves occurring at an angle ____________ 90 degree then they are called as bow shock.

a) less than

b) greater than

c) equal to

d) none of the mentioned

Answer: b

Explanation: When normal shock waves occurring at an angle less than 90 degree they are called as oblique shock waves.

10. When oblique shock _________ the flow it is called as a bow shock.

a) detached from

b) added to

c) minimizes

d) none of the mentioned

Answer: a

Explanation: Due to flow conditions oblique shock may be attached or detached with flow, When oblique shock wave is detached with the flow it forms a bow shock.

This set of Steam and Gas Turbines Multiple Choice Questions & Answers  focuses on “The Diffuser and Prewhirl”.

1. Gas turbine diffuser _________ the production of energy.

a) increases

b) decreases

c) remains constant

d) none of the mentioned

Answer: b

Explanation: Gas turbine diffuser increases the production of energy.

2. Gas turbine diffusers ________ the speed of the flow.

a) increases

b) reduces

c) remains constant

d) none of the mentioned

Answer: a

Explanation: Gas turbine diffuser increases the speed of the flow.

3. Movement speed of motor shaft is _________ when diffuser is used.

a) decreased

b) increased

c) remains constant

d) none of the mentioned

Answer: b

Explanation: Motor shaft speed is increased when diffuser is used. When diffuser is used it converts the pressure energy of the gas into rotation of motor shaft and diffuses the working fluid.

4. In automobiles diffuser _________ the down force.

a) decrease

b) minimizes

c) increases

d) none of the mentioned

Answer: c

Explanation: In automobiles diffuser allow the air to escape from outside and as a result down force increases.

5. In jet engines diffusers are used __________

a) At low speeds

b) At Supersonic speeds

c) Not related to speed at all

d) None of the mentioned

Answer: b

Explanation: Diffuser allows extra air to escape and as a result aerodynamic properties increases and hence diffuser is used in jet engine when operated at supersonic speeds.

6. Diffuser is installed after turbine where air passes the turbine first then passes through diffuser.

a) True

b) False

Answer: b

Explanation: Diffuser is installed between vanes and turbine where air after passing through the diffuser enters the vanes.

7. In centrifugal compressor diffuser is used in a channel ________ the vanes.

a) before

b) after

c) between

d) none of the mentioned

Answer: c

Explanation: In a centrifugal compressor diffuser is used in a channel between vanes.

8. Diffusers are also used in underwater breathing systems.

a) True

b) False

Answer: a

Explanation: Diffusers are used in under water breathing systems so that bubble formation is reduced.

9. Diffuser ___________ velocity air.

a) depends o the situation

b) slows

c) increases

d) none of the mentioned

Answer: c

Explanation: Diffuser is used in compressor section and slows down the high velocity air and increases the pressure.

10. Diffuser changes the ______________ to longitudinal direction.

a) parallel flow

b) radial direction

c) perpendicular flow

d) none of the mentioned

Answer: b

Explanation: Diffuser changes the radial air flow direction into longitudinal direction.

This set of Steam and Gas Turbines Multiple Choice Questions & Answers  focuses on “Performance Characteristics”.

1. In Compressor jet propulsion cycles pressure energy is added to the air steam.

a) True

b) False

Answer: a

Explanation: In compressor jet propulsion cycle pressure energy is added to the air steam.

2. Pressure energy is added to the air steam at _________ pressure ratios in compressor jet propulsion cycles.

a) high

b) low

c) medium

d) none of the mentioned

Answer: b

Explanation: Pressure energy is added to the air steam at low pressure ratios on compressor jet propulsion cycles.

3. The super critical steam first _________ while flowing through the turbine.

a) expands

b) expands & contracts

c) contracts

d) none of the mentioned

Answer: a

Explanation: Super critical steam expands while flowing through a turbine.

4. Turbine exhaust is connected to the ________

a) condenser

b) compressor

c) condenser & compressor

d) none of the mentioned

Answer: a

Explanation: The turbine exhaust is connected to the condenser where heat of vaporization is used.

5. In jet propulsion cycles _______ is used as working fluid.

a) water

b) methane

c) water & methane

d) none of the mentioned

Answer: a

Explanation: Water is used as working fluid in jet propulsion cycles.

6. In jet propulsion cycle specific impulse is ___________

a) high

b) low

c) medium

d) none of the mentioned

Answer: b

Explanation: In jet propulsion cycle specific impulse is low which is a major disadvantage.

7. When reactor pressure is increased above 400psi its performance is ___________

a) decreased

b) remains constant

c) increased

d) none of the mentioned

Answer: c

Explanation: When reactor pressure is increased above 400psi its performance is increased.

8. When reactor steam outlet pressure is increased performance is increased __________

a) Rapidly

b) Little

c) Pressure remains constant

d) None of the mentioned

Answer: b

Explanation: When reactor steam outlet pressure is increased performance is increased very little.

9. Specific impulse in jet propulsion is ________

a) low

b) high

c) medium

d) none of the mentioned

Answer: a

Explanation: Specific impulse was found to be low in jet propulsion cycles.

10. When condenser pressure is increased performance is _______

a) decreased

b) increased

c) remains constant

d) none of the mentioned

Answer: b

Explanation: When condenser pressure is increased performance also increases a little.

This set of Steam and Gas Turbines Multiple Choice Questions & Answers  focuses on “Pressure Coefficients and Slip Factor”.

1. Fluid slip in the impeller can be measured by ____________

a) Pressure coefficient

b) Slip factor

c) Pressure coefficient & Slip factor

d) None of the mentioned

Answer: b

Explanation: Fluid slip in the impeller can be measured by slip factor.

2. Deviation in the angle of the fluid leaving the impeller is called as _________

a) slip factor

b) pressure rise

c) fluid slip

d) none of the mentioned

Answer: c

Explanation: The deviation in the angle of the fluid leaving the impeller is called fluid slip.

3. In axial impellers fluid slip is ______

a) Small

b) Large

c) Medium

d) None of the mentioned

Answer: a

Explanation: In axial impellers fluid slip is quite small.

4. In radial impellers fluid slip is _________

a) Small

b) Large

c) Medium

d) None of the mentioned

Answer: b

Explanation: In radial impellers fluid slip is large.

5. Back eddy is also responsible for ___________

a) slip factor

b) mean blade loading

c) slip factor & mean blade loading

d) none of the mentioned

Answer: a

Explanation: Back eddy is also responsible for slip factor.

6. Mean blade loading is also responsible for ___________

a) back eddy

b) slip factor

c) back eddy & slip factor

d) none of the mentioned

Answer: b

Explanation: Mean blade loading is responsible for slip factor.

7. Working fluid viscosity is also responsible for _________

a) slip factor

b) mean blade loading

c) back eddy

d) none of the mentioned

Answer: a

Explanation: Working fluid viscosity is also responsible for slip factor.

8. Boundary layer blockage is responsible for __________

a) back eddy

b) mean blade loading

c) slip factor

d) none of the mentioned

Answer: a

Explanation: Boundary layer blockage is also responsible for slip factor.

9. Slip factor is the ratio of ideal whirl velocity to actual whirl velocity.

a) True

b) False

Answer: b

Explanation: Slip factor is the ratio of actual whirl velocity to the ideal whirl velocity.

10. When blade angle decreases slip factor also __________

a) decreases

b) remains constant

c) increases

d) none of the mentioned

Answer:c

Explanation: When blade angle decreases slip factor increases.

This set of Steam and Gas Turbines Multiple Choice Questions & Answers  focuses on “Surging”.

1. A back flow from discharge to suction in compressor is called as __________

a) Pitching

b) Yawning

c) Surging

d) None of the mentioned

Answer: c

Explanation: Back flow of working fluid from discharge section to suction in compressor is called as surging.

2. Surging occurs when mass flow crosses ________

a) critical value

b) peak pressure

c) below critical value

d) none of the mentioned

Answer: b

Explanation: Surging occurs when mass flow falls below the critical value.

3. Surging occurs when pressure difference is ________

a) high

b) low

c) medium

d) none of the mentioned

Answer: a

Explanation: When surging is occurred high pressure difference is established.

4. Surging _________ the speed of rotation.

a) increases

b) decreases

c) remains constant

d) none of the mentioned

Answer: b

Explanation: Surging decreases the speed of the rotation.

5. Surging produces _______ vibrations.

a) heavy

b) little

c) medium range

d) none of the mentioned

Answer: a

Explanation: Surging produces heavy vibrations due to forward and backward flow of fluid.

6. Surging effects the working of __________

a) compressor

b) turbine

c) surging

d) none of the mentioned

Answer: d

Explanation: Surging effects working of compressor.

7. Surging also damages pipelines.

a) True

b) False

Answer: a

Explanation: Surging damages the pipelines due to vibration produced.

8. Due to surging when pressure changes_________ turbine shuts down.

a) very high

b) very low

c) to zero

d) none of the mentioned

Answer: b

Explanation: Due to surging when the pressure drops very low turbine may shut down.

9. Surging only ________ the speed.

a) increases

b) increases & decreases

c) decreases

d) none of the mentioned

Answer: c

Explanation: Surging not only reduces the speed sometimes it leads to overspeed.

10. Surging can be prevented by anti surge systems and control valve.

a) True

b) False

Answer: a

Explanation: Surging can be prevented by anti surge systems and control valve.

This set of Steam and Gas Turbines Multiple Choice Questions & Answers  focuses on “Centrifugal Compressors Design Calculations”.

1. No of dimensions used in centrifugal compressors are ____________

a) 1

b) 2

c) 3

d) 4

Answer: c

Explanation: Centrifugal compressors use three dimensions. They are

Mass

Length

Time.

2. Flow in a centrifugal compressor is inversely proportional to _______

a) Time

b) Square of time

c) Cube of time

d) None of the mentioned

Answer: a

Explanation: Flow in centrifugal compressor is inversely proportional to the time.

3. Head in centrifugal compressor is __________ to square of the time.

a) directly proportional

b) equal to

c) inversly proportional

d) none of the mentioned

Answer: c

Explanation: Head in centrifugal compressor is inversely proportional to square of the time.

4. Continuity equation can be applied to centrifugal compressor.

a) True

b) False

Answer: a

Explanation: Continuity equation also known as conservation of mass can be applicable to centrifugal compressor.

5. Navier stokes equation is conservation of ____________

a) Mass

b) Momentum

c) Mass & Momentum

d) None of the mentioned

Answer: b

Explanation: Navier stokes equation is conservation of momentum.

6. Centrifugal compressor is an __________

a) irreversible process

b) quasi static process

c) reversible process

d) none of the mentioned

Answer: c

Explanation: Under some circumstances centrifugal compressor is reversible process.

7. In centrifugal compressor flow is ____________

a) radial

b) Perpendicular

c) radial & Perpendicular

d) none of the mentioned

Answer: a

Explanation: In centrifugal compressor flow is radial.

8. In centrifugal compressor centrifugal energy present in the gas is utilized to ___________

a) compress

b) increase temperature

c) radial

d) none of the mentioned

Answer: a

Explanation: In centrifugal compressor centrifugal energy present in the gas is utilized to do work.

9. Centrifugal compressor delivers ____________ flow capacity.

a) high

b) low

c) medium

d) none of the mentioned

Answer: b

Explanation: Centrifugal compressor delivers low flow capacity.

10. Rotating speed of centrifugal compressor is __________ function of diameter to be maintained.

a) inverse

b) direct

c) point

d) none of the mentioned

Answer: a

Explanation: Rotating speed of centrifugal compressor is inverse function of diameter to be maintained.

This set of tough Steam and Gas Turbines Questions focuses on “Combustion and Thermochemistry”.

1. Combustor is also known as __________

a) flame holder

b) burner

c) flame holder & burner

d) none of the mentioned

Answer: a

Explanation: Combustion takes place in combustor. It is also known as flame holder. Combustor can also be called as burner. Flame holder is used to hold the flame in the combustor.

2. In gas turbine combustion chamber is fed with __________ pressure high temperature gas.

a) low

b) high

c) medium

d) none of the mentioned

Answer:b

Explanation: In gas turbine combustor is fed with high pressure gas. As the pressure is very high as soon as oxygen is supplied in fuel starts burning.

3. When combustor pressure decreases efficiency _________

a) increases

b) decreases

c) remains constant

d) none of the mentioned

Answer: b

Explanation: When combustor pressure decreases its efficiency decreases as it is directly proportional.

4. In an ideal combustor exit temperature must be _________

a) decreasing

b) increasing

c) constant

d) none of the mentioned

Answer: c

Explanation: When exit temperature is not uniform thermal stress develops on the walls of combustor.

5. In air crafts combustors are constrained by size and weight.

a) True

b) False

Answer:a

Explanation: In air craft combustors are constrained by size and weight.

6. Combustors ________ pollutants.

a) increase

b) decrease

c) remains constant

d) none of the mentioned

Answer: b

Explanation: Combustors reduce pollutants. The work of combustor is to assure that fuel is completely burned, when the fuel is completely burned pollutants will be reduced.

7. Swirler is the _____ part in the combustor.

a) first

b) middle

c) last

d) none of the mentioned

Answer: a

Explanation: When air enters combustor it firstly passes through swirler where it induces swirling motion.

8. Nitrogen oxides are released from ________

a) combustors

b) burners

c) combustors & burners

d) none of the mentioned

Answer: c

Explanation: Nitrogen oxide is also a type of pollutant released from combustor.

9. CO pollutant released from combustor is emitted during _______ process.

a) reduction

b) oxidation

c) co is released no where

d) none of the mentioned

Answer: b

Explanation: Carbon monoxide is released during oxidizing process.

10. Nitrogen oxides are produced during combustion zone.

a) True

b) False

Answer: a

Explanation: Nitrogen oxides are produced during combustion zone.

This set of Steam and Gas Turbines Multiple Choice Questions & Answers  focuses on “Entropy, Chemical Equilibrium and Heat of Reaction”.

1. The total specific ways in which a thermodynamic system can be arranged is called as ___________

a) entropy

b) enthalpy

c) specific volume

d) none of the mentioned

Answer: a

Explanation: The total specific ways in which a system can be arranged is called entropy.

2. Measure of disorderness is called ________

a) pressure

b) enthalpy

c) entropy

d) none of the mentioned

Answer: c

Explanation: Entropy is the measure of randomness.

3. Entropy of a closed system __________

a) decreases

b) increases

c) remains constant

d) none of the mentioned

Answer:b

Explanation: Entropy of a closed system always increases.

4. During thermodynamic equilibrium entropy is _________ in isolated system.

a) minimum

b) zero

c) maximum

d) none of the mentioned

Answer: c

Explanation: During thermodynamic equilibrium entropy is maximum in isolated system.

5. Entropy is a _______ function.

a) state

b) path

c) point

d) none of the mentioned

Answer: a

Explanation: Entropy is a state function.

6. Entropy is an ___________

a) intensive property

b) extensive property

c) intensive & extensive property

d) none of the mentioned

Answer: b

Explanation: Entropy is an extensive property.

7. Units of entropy are same as of units of energy.

a) True

b) False

Answer: a

Explanation: Energy and Entropy both have same units.

8. Entropy of a pure substance is an ____________

a) point function

b) extensive property

c) intensive property

d) none of the mentioned

Answer: c

Explanation: Entropy of a pure substance is an intensive property. Entropy of pure substances is only intensive if the substance is not pure then the entropy is extensive property.

9. Thermodynamic entropy differs from statistical mechanics entropy by a constant __________

a) Critical pressure

b) Critical pressure & Boltzmann’s constant

c) Boltzmann’s constant

d) None of the mentioned

Answer: c

Explanation: Thermodynamic entropy differs from statistical mechanics entropy differs by a boltzmann’s constant.

10. Perpetual motion machines are derived from the concept of entropy.

a) True

b) False

Answer: a

Explanation: Perpetual motion machines are derived from the concept of entropy.

This set of Steam and Gas Turbines Multiple Choice Questions & Answers  focuses on “Flame Temperature and Dissociation”.

1. Flame temperature is the __________ temperature reactants can achieve during combustion.

a) minimum

b) maximum

c) constant

d) none of the mentioned

Answer: b

Explanation: Flame temperature is the maximum temperature reactants can achieve during combustion process.

2. Incomplete combustion results in _________ flame temperature.

a) lower

b) higher

c) medium

d) none of the mentioned

Answer: a

Explanation: Incomplete combustion results in lower flame temperature. When the fuel is incompletely combusted the remains the previous combustion will be there in the combustion chamber and when the next cycle starts previous remains also start combusting and as they are at some high temperatures flame temperature gets reduced.

3. Heat transfer results in _________ flame temperature.

a) medium

b) higher

c) lower

d) none of the mentioned

Answer: c

Explanation: Heat transfer results in lower flame temperature. When heat starts transferring amount of heat present in fluid gets reduced and hence flame temperature also gets reduced.

4. __________ flame temperature is attained during stoichiometric mixture.

a) minimum

b) maximum

c) medium

d) none of the mentioned

Answer:b

Explanation: Perfect stoichiometric mixture results in achieving maximum flame temperature.

5. At the end of the combustion process flame temperature deviation is _________

a) high

b) low

c) medium

d) none of the mentioned

Answer: a

Explanation: At the end of combustion process temperature deviation is high. During the end of combustion all the fuel and oxygen gets completed and hence rate of combustion gets reduced as a result flame temperature is drastically reduced.

6. Dissociation of reactants ________ flame temperature.

a) maximizes

b) minimizes

c) remains constant

d) none of the mentioned

Answer: b

Explanation: Dissociation of reactants decreases the flame temperatures. For reactants to dissociate it requires some heat energy and as a result flame temperature is decreased.

7. During combustion entropy change between initial and final state is ____________

a) zero

b) maximum

c) minimum

d) none of the mentioned

Answer: a

Explanation: During combustion entropy change between initial and final state is zero.

8. When flame temperature _________ combustion rate decreases.

a) not related to each other

b) decreases

c) increases

d) none of the mentioned

Answer: c

Explanation: When flame temperature increases combustion rate decreases. When combustion is going to complete it uses up all the oxygen present in the chamber so that flame temperature is increased.

9. Fuel/air ratio effects flame temperature.

a) True

b) False

Answer: a

Explanation: Fuel to air ratio effects flame temperature.

10. When specific heat increases flame temperature ________

a) decreases

b) increases

c) remains constant

d) none of the mentioned

Answer: b

Explanation: When specific heat increases flame temperature increases.

This set of Steam and Gas Turbines Multiple Choice Questions & Answers  focuses on “Mechanics of Combustion”.

1. In combustion the _______________ is released from breaking the chemical bonds.

a) chemical energy

b) heat energy

c) kinetic energy

d) none of the mentioned

Answer: a

Explanation: When required heat energy is supplied chemical bonds break and release energy.

2. In combustion mechanism chain branching is represented by ______

a) g

b) f

c) a

d) t

Answer: b

Explanation: In combustion mechanism chain branching is represented by f.

3. In combustion mechanism chain termination is represented by ________

a) t

b) b

c) g

d) f

Answer: c

Explanation: In combustion mechanism chain termination is represented by g.

4. If g is _______ than f then termination exceeds branching.

a) greater

b) lesser

c) equal

d) none of the mentioned

Answer:a

Explanation: If g is greater than f then termination exceeds branching.

5. If f is ___________ than g then branching exceeds termination.

a) equal

b) lesser

c) greater

d) none of the mentioned

Answer: c

Explanation: If f is greater than g then branching exceeds termination.

6. Low oxygen pressures assures g _________ f.

a) lesser than

b) greater

c) equal to

d) none of the mentioned

Answer: b

Explanation: Low oxygen pressures assure g greater than f.

7. High oxygen pressure assure g ________ f.

a) lesser than

b) greater than

c) equal to

d) none of the mentioned

Answer: a

Explanation: High oxygen pressure assure g less than f.

8. Rate of combustion depends upon radial concentration.

a) True

b) False

Answer: a

Explanation: Rate of combustion depends upon radial concentration.

9. Hydrogen oxygen reaction depends upon ________

a) pressure concentration

b) temperature gradient

c) temperature

d) none of the mentioned

Answer: a

Explanation: Hydrogen oxygen reaction depends on pressure.

10. Hydrocarbon combustion is of __________

a) two

b) one

c) three

d) none of the mentioned

Answer: a

Explanation: Hydrocarbon combustion is of two types. They are hydro carbon breaking and oxidizing.

This set of Steam and Gas Turbines Quiz focuses on “Physical Characteristics of Combustion and Reactive Mixtures, Pressure Losses”.

1. Inert character of nitrogen __________ the commercial value of gas.

a) decreases

b) increases

c) remains same

d) none of the mentioned

Answer: a

Explanation: Inert character of nitrogen decreases the commercial value of gas. Inert gases can not be used in all circumstances.

2. Carbon dioxide released is __________ in nature.

a) not corrosive

b) corrosive

c) depends on the usage

d) none of the mentioned

Answer: b

Explanation: Carbon dioxide released from combustion has corrosive properties.

3. Hydrogen sulfide released during combustion is __________ in nature.

a) not corrosive

b) corrosive

c) depends on the usage

d) none of the mentioned

Answer: b

Explanation: Hydrogen sulfide released during combustion have corrosive properties.

4. In combustion it is assumed that there is ____________

a) atomic attraction

b) no atomic attraction

c) molecular attraction

d) none of the mentioned

Answer: a

Explanation: From kinetic theory of gases it is assumed that atomic attractions are negligible.

5. In combustion it is assumed that the number of molecules for unit volume is ___________

a) constant

b) decreased

c) increased

d) none of the mentioned

Answer: c

Explanation: From kinetic theory of gases it is assumed that the number of molecules for unit volume are constant. Volume and density does not change on phase change is occurred.

6. In combustion between two shocks motion is rectilinear.

a) True

b) False

Answer: a

Explanation: In combustion between two shocks motion is rectilinear.

7. Euken number is introduced in _______ atomic gases.

a) mono

b) poly

c) di

d) none of the mentioned

Answer: b

Explanation: Euken number is introduced in poly atomic gases and mono atomic gases also.

8. For mono atomic gases euken number is approximately _________

a) 5

b) 3

c) 4

d) 2.5

Answer: d

Explanation: For mono atomic gases euken number is approximately 2.5

9. Inter changeability of gases gives _________

a) wobbe index

b) euken number

c) wobbe index & euken number

d) none of the mentioned

Answer: a

Explanation: Wobbe index gives interchangeability of gases during combustion.

10. Methane number is used to define auto ignition.

a) True

b) False

Answer:a

Explanation: Methane number is used to define auto ignition.

This set of Steam and Gas Turbines MCQs focuses on “The Combustor”.

1. Combustor is also called as _________

a) combustion

b) ramjet

c) inlet manifold

d) none of the mentioned

Answer: a

Explanation: Combustor is also called as a ramjet. Inlet manifold is the inlet pipe provided for adding materials.

2. Combustor can also be called as __________

a) burner

b) ramjet

c) inlet manifold

d) none of the mentioned

Answer: b

Explanation: Combustor can be called as ramjet or burner.

3. Pressure inside the combustor is ________

a) Constant

b) Increases

c) Decreases

d) None of the mentioned

Answer: a

Explanation: Pressure inside the combustor is constant.

4. In _________ air is directly fed to the nozzle.

a) burner & ramjet

b) burner

c) ramjet

d) none of the mentioned

Answer: c

Explanation: In ramjet air is directly fed to the nozzle. Ramjet or burner both mean the same.

5. Flow rates are ________ in combustor.

a) high

b) low

c) medium

d) none of the mentioned

Answer: a

Explanation: Flow rates are high in the combustors. As pressure is high flow rate is also high in the combustor.

6. When 1 kg of jet fuel is produced _______ amount of co 2 is released.

a) 3kg

b) 3.2kg

c) 3.4kg

d) 3.8kg

Answer: b

Explanation: When 1 kg of jet fuel is burned 3.2 kgs of co 2 is released.

7. Fuel that was not completely burnt is called as _______

a) Ramjets

b) UHC

c) Emissions

d) None of the mentioned

Answer: b

Explanation: Incompletely combusted fuels are called as UHC.

8. UHC’s are produced at _________ power levels.

a) high

b) medium

c) low

d) none of the mentioned

Answer: c

Explanation: UHC’s are generally produced at low power levels.

9. Combustors which doesn’t produce more CO doesn’t emit much UHC.

a) True

b) False

Answer: a

Explanation: Combustors that have highly optimized UHC are the combustors which produce low CO emissions.

10. CO produced in combustion is eliminated by __________

a) reduction

b) oxidation

c) reduction & oxidation

d) none of the mentioned

Answer: b

Explanation: CO produced in combustion is eliminated by oxidation.

This set of Steam and Gas Turbines Multiple Choice Questions & Answers  focuses on “Fuel Injection, Atomization and Combustion Chamber”.

1. Nozzles are also a part of gas turbine _________

a) combustor

b) compressor

c) fuel injection

d) none of the mentioned

Answer: c

Explanation: In gas turbine fuel injection nozzles are used for atomization.

2. ___________ are present in gas turbine fuel injectors.

a) Vaporizers

b) Recuperators

c) Nozzles

d) None of the mentioned

Answer: a

Explanation: Vaporizers are also a part of fuel injectors.

3. ____________ are also a part of gas turbine fuel injectors.

a) Swirlers

b) Nozzles

c) Recuperators

d) None of the mentioned

Answer: b

Explanation: Swirlers present in gas turbine fuel injectors turns the movement of gas inside the injector to swirling motion so that combustion efficiency is high. Nozzles are used to inject fuel.

4. Afterburner spray bars are present in gas turbine fuel injectors.

a) True

b) False

Answer: a

Explanation: Afterburner spray bars are present in fuel injectors.

5. When fuel injectors efficiency is optimized then overall efficiency of gas turbines is __________

a) remains constant

b) decreased

c) increased

d) none of the mentioned

Answer: c

Explanation: When fuel injectors efficiency is optimized then overall efficiency of gas turbines is increased.

6. __________ of engines are determined from fuel injectors.

a) Efficiency

b) Emissions

c) Efficiency & Emissions

d) None of the mentioned

Answer: c

Explanation: Fuel injectors also plays a major role in defining emissions. Working of fuel injectors determines both emissions and efficiency.

7. Lean mixtures give _________ efficiency.

a) optimal

b) higher

c) lower

d) none of the mentioned

Answer: a

Explanation: Lean mixture give optimal efficiency.

8. In low fuel combustion lean mixture have _______ efficiency.

a) high

b) low

c) medium

d) none of the mentioned

Answer: b

Explanation: In low fuel combustion lean mixture have low efficiency.

9. Fuel droplet size effects the _________

a) combustion

b) effects

c) combustion & effects

d) none of the mentioned

Answer: a

Explanation: When fuel droplet size is minimized combustion is maximized. Combustion directly effects the efficiency of the gas turbine.

10. Airflow controls the rate of combustion.

a) True

b) False

Answer: a

Explanation: Airflow determines the mixture of fuel which controls the rate of combustion.

This set of Steam and Gas Turbines Multiple Choice Questions & Answers  focuses on “The Regenerator”.

1. In regenerator energy is stored in ___________

a) gas medium

b) fluid medium

c) thermal medium

d) none of the mentioned

Answer: b

Explanation: In regenerator energy is stored in the thermal medium.

2. Both hot and cold fluid used in regenerators is __________

a) same fluid

b) different fluid

c) depending on the situation

d) none of the mentioned

Answer:a

Explanation: Both hot and cold fluid used in regenerators is the same fluid.

3. Heat regenerators are ___________

a) dependent

b) repetitive

c) costant

d) none of the mentioned

Answer: c

Explanation: Heat regenerators are repetitive.

4. Rotatary regenerators are _________ flow path.

a) parallel

b) counter flow path

c) repetitive

d) none of the mentioned

Answer: b

Explanation: Rotatry regenerators have counter flow path.

5. In a fixed matrix regenerator flow is __________

a) reversible

b) irreversible

c) repetitive

d) none of the mentioned

Answer: a

Explanation: In a fixed matrix regenerator flow is reversible. In fixed matrix regenerator flow can be in both directions depending on the requirement.

6. In a fixed flow regenerator flow is __________

a) repetitive

b) counter

c) parallel

d) none of the mentioned

Answer: c

Explanation: In a fixed flow regenerator flow is counter current.

7. Fixed matrix regenerator is a part of ________ system.

a) valveless

b) valve

c) depending on the requirement

d) none of the mentioned

Answer: a

Explanation: Fixed matrix regenerators is a part of valveless system. In fixed matrix flow is reversible.

8. Rothemuhle regenerator has same design of _________ regenerator.

a) fixed matrix

b) varying matrix

c) varying & fixed matrix

d) none of the mentioned

Answer: a

Explanation: Rothemuhle regenerator has same design of fixed matrix regenerator.

9. Regenerators used in cryogenics are ________

a) small

b) large

c) medium

d) none of the mentioned

Answer: b

Explanation: Regenerators used in cryogenics are large. Cryogenic engines require large structures.

10. Regenerators have lower surface area than recuperator.

a) True

b) False

Answer: b

Explanation: Regenerators have higher surface area than recuperators.

This set of Steam and Gas Turbines Multiple Choice Questions & Answers focuses on “Regenerator Types and Mean Temperature Difference”.

1. In rotary regenerators matrix is __________

a) constant

b) varying

c) zero

d) none of the mentioned

Answer: b

Explanation: In rotary regenerators matrix rotates continuously.

2. In rotary regenerators matrix is ________

a) isothermal

b) isochoric

c) constant pressure process

d) none of the mentioned

Answer: a

Explanation: In rotary regenerators matrix is isothermal.

3. In rotary regenerators rotation is _________ to the flow direction.

a) parallel

b) perpendicular

c) concurrent

d) none of the mentioned

Answer: b

Explanation: In rotary regenerator rotation is always perpendicular to the flow direction.

4. In rotary regenerator rotation is __________ to the temperature gradient.

a) parallel

b) congruent

c) perpendicular

d) none of the mentioned

Answer:c

Explanation: In rotary regenerator rotation is always perpendicular to both temperature gradient and flow direction.

5. In rotary regenerators fluid temperature is __________ across the flow area.

a) constant

b) varying

c) zero

d) none of the mentioned

Answer: b

Explanation: In rotary regenerators fluid temperature varies across the flow area.

6. In fixed matrix regenerator the fluid is ducted to the valves to flow through various matrices.

a) True

b) False

Answer: a

Explanation: In fixed matrix regenerator the fluid is ducted to the valves to flow through various matrices.

7. Outlet temperatures of fixed matrix regenerator is ______ with time.

a) constant

b) varying

c) zero

d) none of the mentioned

Answer: b

Explanation: Outlet temperatures of the fixed matrix regenerator varies with time.

8. Micro scale regenerator has multi grating structure.

a) True

b) False

Answer: a

Explanation: Micro scale regenerator has multi grating structure.

9. In micro scale regenerator each layer is _______ from the adjacent layer.

a) equal

b) subset

c) offset

d) none of the mentioned

Answer: c

Explanation: In micro scale regenerator each layer is offset from the adjacent layer.

10. Rothemuhle regenerator has a _______ matrix in a disk shape.

a) moving

b) fixing

c) no matrix

d) none of the mentioned

Answer: b

Explanation: Rothemuhle regenerator has a fixed matrix in a disk shape.

This set of Steam and Gas Turbines online test focuses on “Film Coefficient, Pressure Losses and Regenerator Effectiveness”.

1. Film coefficient is also known as heat transfer coefficient.

a) True

b) False

Answer: a

Explanation: Film coefficient is also known as heat transfer coefficient.

2. Film coefficient is the proportionality coefficient between heat flux and ___________

a) opposing force

b) driving force

c) opposing & driving force

d) none of the mentioned

Answer: b

Explanation: Film coefficient is the proportionality coefficient between heat flux and driving force.

3. Film coefficient is represented by _______

a) t

b) g

c) h

d) f

Answer: c

Explanation: Heat transfer coefficient is represented by h.

4. ___________ is used in phase transition process.

a) Film coefficient

b) Pressure coefficient

c) Mean temperature

d) None of the mentioned

Answer: a

Explanation: Film coefficient is used in phase transition process.

5. Film coefficient is _________ of thermal insulance.

a) directly proportional

b) inverse

c) equal

d) none of the mentioned

Answer: b

Explanation: Film coefficient is inverse of thermal insulance. Film coefficient is the inverse of the resistance offered by the material towards heat.

6. Ratio of thermal conductivity to the length scale is known as __________

a) Film coefficient

b) Heat transfer coefficient

c) Film & Heat transfer coefficient

d) None of the mentioned

Answer: c

Explanation: Ratio of thermal conductivity to length is known as film coefficient.

7. Nusselt number has ________

a) no dimension

b) dimension

c) no units

d) none of the mentioned

Answer: a

Explanation: Nusselts number is a dimensionless number. Nusselt’s number is used in calculating heat transfer.

8. Overall heat transfer coefficient is represented by _______

a) K

b) A

c) U

d) I

Answer: c

Explanation: Overall heat transfer coefficient is represented by U.

9. Nusselts number applies to _______

a) Laminar flow

b) Turbulent flow

c) Laminar & Turbulent flow

d) None of the mentioned

Answer: c

Explanation: Nusselts number is applicable to both laminar and turbulent flow.

10. Mass flux is denoted by ______

a) J

b) G

c) U

d) None of the mentioned

Answer: a

Explanation: Mass flux is represented by j.

This set of Steam and Gas Turbines Multiple Choice Questions & Answers  focuses on “Economic Aspect of Regenerator Design”.

1. In two stat regenerator system ________ stage is known as partial combustion mode.

a) first

b) last

c) intermediate

d) none of the mentioned

Answer: a

Explanation: In two stage regenerator system first stage combusts CO with all the available oxygen.

2. Amount of coke burnt is _______ in first stage of two stage regenerator.

a) varied

b) constant

c) Zero

d) none of the mentioned

Answer: b

Explanation: Amount of coke burned varies in first stage of two stage regenerator.

3. In two stage regenerators catalyst deactivation rates are _______

a) low

b) high

c) medium

d) none of the mentioned

Answer: a

Explanation: The environment produced in two stage regenerator is gentle and hence catalyst deactivation rates are low.

4. ________ catalyst deactivation rates are benefited as catalysts are poisonous in nature.

a) medium

b) high

c) less

d) none of the mentioned

Answer: c

Explanation: Less catalyst deactivation rates are benefited as catalysts are poisonous in nature.

5. In two stage regenerator system catalyst cooler is added.

a) True

b) False

Answer: a

Explanation: In a two stage regenerator system a catalyst cooler is present.

6. Cooling capacity of catalyst cooler is _________ MMBtu/h.

a) 120

b) 100

c) 140

d) 200

Answer: c

Explanation: Cooling capacity of catalyst cooler is 140MMBtu/h.

7. When cooling system is needed to be increased no of catalyst coolers are _________ by two or three.

a) increased

b) decreased

c) not related

d) none of the mentioned

Answer: a

Explanation: When cooling system is needed to be increased no of catalyst coolers are increased to two or three.

8. In two stage FCC regenerator FCC stands for fluid catalytic cracking unit.

a) True

b) False

Answer: a

Explanation: In two stage FCC regenerator FCC stands for fluid catalytic cracking unit.

9. Total no of FCC regenerators operated in India are ______

a) 20

b) 10

c) 5

d) 15

Answer: b

Explanation: Total no of 10 FCC regenerators are operated India.

10. Minimum obtained catalyst loss is ________ Kg/day.

a) 500

b) 400

c) 420

d) 360

Answer: c

Explanation: Minimum obtained catalyst loss is 420kg/day.

This set of Steam and Gas Turbines Multiple Choice Questions & Answers  focuses on “Power Plant”.

1. Land based gas turbines are classified into _________ types.

a) 3

b) 2

c) 4

d) 6

Answer: b

Explanation: Land based gas turbines are sub divided into two types.

2. Heavy frame engines are a type of _______ based gas turbines.

a) land

b) vertical

c) air

d) none of the mentioned

Answer: a

Explanation: Heavy frame engines are type of land based engines.

3. Aero derivative engines are _________ based gas turbines.

a) air

b) vertical

c) land

d) none of the mentioned

Answer: c

Explanation: Aero derivative engines are land based gas turbines.

4. Heavy frame engines have _______ pressure ratios.

a) low

b) high

c) medium

d) none of the mentioned

Answer: a

Explanation: Heavy frame engines have low pressure ratios. Heavy frame engines work under low pressure ratios.

5. Aero derivative engines have _________ pressure ratios.

a) low

b) high

c) medium

d) none of the mentioned

Answer: b

Explanation: Aero derivative engines have higher pressure ratios. Heavy frame engines work under low pressure ratios.

6. Minimum compression ratio of aero derivative engines are ______

a) 20

b) 40

c) 30

d) 60

Answer: c

Explanation: Minimum compression ratio of aero derivative engines are 30.

7. Aero derivative engines are very ________ in size.

a) large

b) small

c) medium

d) none of the mentioned

Answer: b

Explanation: Aero derivative engines are very compact. That is why aero derivative engines have high pressure ratios.

8. _______ temperatures in gas turbines gives low efficiency.

a) low

b) high

c) medium

d) none of the mentioned

Answer: a

Explanation: High temperature in gas turbines gives high efficiency.

9. Temperatures in gas turbines are about _______

a) 1500 F

b) 1000 F

c) 2300 F

d) 1800 F

Answer: c

Explanation: Temperatures in gas turbines are about 2300F.

10. When inlet temperature is increased to 2600F then efficiency is about ____________

a) 20%

b) 30%

c) 80%

d) 60%

Answer: d

Explanation: When inlet temperature is increased to 2600F then efficiency is about 60%.

This set of Steam and Gas Turbines Multiple Choice Questions & Answers  focuses on “Dimensionless Performance Parameters”.

1. Dimensional analysis can be used to compare gas turbines.

a) True

b) False

Answer: a

Explanation: Dimensionless analysis can be used to compare gas turbines.

2. Reynolds number is a __________ parameter.

a) constant

b) have dimension

c) dimensionless constant

d) none of the mentioned

Answer: c

Explanation: Reynolds number is a dimensionless parameter.

3. Power is expressed in ___________

a) Horsepower

b) Volts

c) Ohms

d) None of the mentioned

Answer: a

Explanation: Power is expressed in horsepower.

4. Flow coefficient has no _______

a) value

b) dimension

c) flow coefficient is constant

d) none of the mentioned

Answer: b

Explanation: Flow coefficient has no dimension.

5. Pressure coefficient has ___________

a) no value

b) dimension

c) no dimension

d) none of the mentioned

Answer: c

Explanation: Pressure when expressed in dimensionless parameter is called as pressure coefficient.

6. ____________ when expressed in the form of dimensionless quantity is known as flow coefficient.

a) Flow rate

b) Pressure

c) Flow rate & Pressure

d) None of the mentioned

Answer: a

Explanation: Flow coefficient is a dimensionless quantity.

7. Mach number is a _________ parameter.

a) valued

b) dimensionless

c) valued & dimensionless

d) none of the mentioned

Answer: b

Explanation: Mach number is a dimensionless parameter.

8. Gas constants are classified under ________ dimension groups.

a) quasi

b) uni

c) multiple

d) none of the mentioned

Answer:a

Explanation: Gas constants are classified under quasi dimension groups.

9. Corrected groups are __________ proportional to quasi dimension groups.

a) inversely

b) directly

c) not related

d) none of the mentioned

Answer: b

Explanation: Corrected groups are directly proportional to quasi dimensional groups.

10. Working fluid properties are present in scaling parameter groups.

a) True

b) False

Answer: b

Explanation: Working fluid properties are not present in scaling parameter groups.

This set of Steam and Gas Turbines Multiple Choice Questions & Answers  focuses on “Twin Shaft Plant”.

1. SGT700 is a ________ shaft power plant.

a) single

b) twin

c) triple

d) none of the mentioned

Answer: b

Explanation: SGT700 is a twin shaft gas power plant.

2. SGT600 is ________ shaft power plant.

a) single

b) twin

c) multiple

d) none of the mentioned

Answer: a

Explanation: Upgradation of SGT600 that is SGT700 is a twin shaft power plant. SGT600 is a single shaft power plant.

3. Power output of SGT700 plant is __________

a) 30.40MW

b) 36.78MW

c) 32.80MW

d) 38.80MW

Answer: c

Explanation: Power output of SGT700 is 32.82MW.

4. Electrical efficiency of SGT700 is _________

a) 37.2%

b) 38%

c) 39%

d) 40%

Answer: a

Explanation: The electrical efficiency of SGT700 is 37.2%.

5. SGT700 produces _______ noise.

a) high

b) low

c) medium

d) none of the mentioned

Answer: b

Explanation: SGT700 produces low noise.

6. SGT700 produces _______ vibrations.

a) medium

b) low

c) high

d) none of the mentioned

Answer: c

Explanation: SGT700 produces low vibration and low noise.

7. SGT700 is resistant to H 2 S gas.

a) True

b) False

Answer: a

Explanation: SGT700 gas power plant is resistant to H 2 S gas.

8. SGT100 power plant has a power output of ________

a) 10 MW

b) 5 MW

c) 20 MW

d) 25 MW

Answer: b

Explanation: SGT100 has a power output of 5 MW.

9. Gas turbines used for mechanical drives have _______ shaft.

a) single

b) multiple

c) dual

d) none of the mentioned

Answer: c

Explanation: Gas turbines used for mechanical drives use dual shafts.

10. Mechanical drive application have _________ efficiency than electrical applications by 10%.

a) more

b) less

c) both are equal

d) none of the mentioned

Answer: b

Explanation: Mechanical drive application has more efficiency when compared to electrical application by 2%.

This set of Gas Turbines Puzzles focuses on “Dimension Parameters of Aircraft Plants”.

1. Thrust to weight ratio for an airplane is found _______ the takeoff.

a) after

b) before

c) during

d) none of the mentioned

Answer: b

Explanation: Thrust to weight ratio for an airplane is found at the time of intake.

2. Take off mass value for an airplane is found ________ the takeoff.

a) after

b) during

c) before

d) none of the mentioned

Answer: c

Explanation: Take off mass value for an airplane is found before the takeoff during intake. When it is taken after takeoff some fuel might be utilised and mass may be varied.

3. Landing gear for an airplane is selected depending on the engine _________

a) thrust

b) torque

c) torque & thrust

d) none of the mentioned

Answer: a

Explanation: Landing gear for an airplane is selected depending on the engine thrust.

4. Take off mass value also effects the selection of __________

a) drag force & landing gear

b) drag force

c) landing gear

d) none of the mentioned

Answer: c

Explanation: Engine thrust and take off mass value both effects the selection of landing gear.

5. Dimensions of an airplane are effected by the engine _______

a) torque

b) thrust

c) torque & thrust

d) none of the mentioned

Answer: b

Explanation: Dimensions of an airplane can be effected the available engine thrust i.e depending on the engine thrust airplane dimensions are selected.

6. Wing area in an airplane is ________ proportional to take off mass value.

a) not related

b) inversly

c) directly

d) none of the mentioned

Answer: c

Explanation: Wing area of an airplane is directly proportional to take off mass value.

7. Fuel mass required in an airplane is _________ proportional to the take off mass value.

a) directly

b) inversly

c) not related

d) none of the mentioned

Answer: a

Explanation: Fuel mass required in an airplane is directly proportional to the take off value.

8. Fuselage dimensions in an airplane is _________ proportional to cross sectional area of fuselage.

a) inversly

b) directly

c) not related

d) none of the mentioned

Answer: b

Explanation: Fuselage dimensions in an airplane is directly proportional to cross sectional area of fuselage.

9. Rare fuselage length of an airplane is _______ proportional to the diameter of the fuselage.

a) directly

b) inversly

c) not related

d) none of the mentioned

Answer: a

Explanation: Rare fuselage length of an airplane is directly proportional to the diameter of the fuselage.

10. Geometric dimensions of an airplane are required for estimation of the weight of airplane.

a) True

b) False

Answer: a

Explanation: Geometric dimensions of an airplane effects the weight of the airplane.

This set of Steam and Gas Turbines Multiple Choice Questions & Answers  focuses on “Torque Characteristics”.

1. Torque speed characteristics of _______ shaft gas turbine is same as that of dual shaft gas turbine.

a) single

b) multiple

c) double

d) none of the mentioned

Answer: a

Explanation: Torque speed characteristics of single shaft gas turbine is different from the dual shaft gas turbine.

2. In single shaft gas turbine when torque output is 50% engine speed is about _______

a) 50%

b) 80%

c) 90%

d) 100%

Answer: b

Explanation: In a single shaft gas turbine when the engine speed is about 80% the torque is about 50%.

3. In a single shaft gas turbine when the engine speed is about 100% the torque output is ______

a) 40%

b) 50%

c) 80%

d) 100%

Answer: d

Explanation: In a single shaft gas turbine when the engine speed is about 100% the torque output is 100%.

4. In a single shaft gas turbine output shaft is connected to a ________ speed compressor.

a) high

b) low

c) medium

d) none of the mentioned

Answer: a

Explanation: In a single shaft gas turbine output shaft is connected to a high speed compressor.

5. Stability of the rotation in gas turbine compressor is due to ______ inertia.

a) low

b) high

c) medium

d) none of the mentioned

Answer: b

Explanation: Stability of the rotation in gas turbine compressor is due to high inertia.

6. In a dual shaft gas turbine when the speed is about 60% the torque is increased to _______

a) 100%

b) 90%

c) 140%

d) 120%

Answer: c

Explanation: In a double shaft gas turbine when the speed is about 60% the torque is increased to 140%. These values are found from torque and speed curve.

7. In dual shaft gas turbine when the engine speed is 40%, the engine torque is reduced to _________

a) 90%

b) 160%

c) 100%

d) 80%

Answer: b

Explanation: In a dual shaft gas turbine when the engine speed is 40% the torque is increased to 160%. These values are found from graph plotted between torque and speed.

8. Engine output is the ratio of __________ and torque.

a) speed

b) displacement

c) input

d) none of the mentioned

Answer: a

Explanation: Product of speed and torque is known as engine output.

9. At low speeds the output is __________ in dual shaft gas turbine.

a) low

b) medium

c) high

d) none of the mentioned

Answer: c

Explanation: At low speeds the outputs of dual shaft gas turbines are high.

10. In diesel engines engine output increases when engine speed decreases.

a) True

b) False

Answer: b

Explanation: In diesel engines engine output decreases with the decrease in the engine speed.

This set of Steam and Gas Turbines Multiple Choice Questions & Answers  focuses on “Starting and Performance”.

1. In order For turbine to get started air must start flowing ______ to start combustion.

a) outside

b) inside

c) compressing

d) none of the mentioned

Answer: b

Explanation: In a gas turbine in order to start combustion oxygen is required and hence air must start flowing initially.

2. Watt/s is called as a _______

a) joule

b) kilo newton

c) kilo newton/metre

d) none of the mentioned

Answer: a

Explanation: Watt/s is called as a joule.

3. When the amount of energy required is high the life of gas turbine ________

a) not related

b) decreases

c) increases

d) none of the mentioned

Answer: c

Explanation: When the amount of energy required is high the life of gas turbine decreases. Because when amount of power required is high its load increases beyond the limit and hence life decreases.

4. In gas turbines _________ output igniters are used at the starting.

a) low

b) high

c) medium

d) none of the mentioned

Answer: b

Explanation: In gas turbines low output igniters are used when the turbine needs to be run continuously.

5. Electronic igniters can be adjusted as per the required ________

a) output

b) power

c) compressing

d) none of the mentioned

Answer: a

Explanation: Electronic igniters are used as per the required output.

6. When gas turbine is required to operate continuously then power output is ________

a) increased

b) decreased

c) constant

d) none of the mentioned

Answer: b

Explanation: When gas turbine is required to operate continuously the power output is to be reduced as continuous supply of output is needed.

7. When the energy output is __________ igniters life also increases.

a) increased

b) constant

c) decreased

d) none of the mentioned

Answer: c

Explanation: When the igniters life is to be increased then the energy output is decreased. When igniters are used to produce high outputs their life is decreased.

8. Gas turbines has _________ pressure high volume fuel pumps.

a) high

b) low

c) medium

d) none of the mentioned

Answer: b

Explanation: Gas turbines has low pressure and high volume fuel pumps. In gas turbines pressure energy in the working fluid is used to increase volume.

9. In some gas turbines cavitations are _______ by using fuel cooled oil cooler.

a) removed

b) increased

c) cavitations are not caused due to oil cooler

d) none of the mentioned

Answer: a

Explanation: In fuel cooled oil cooler it heats the fuel to high temperature so that the water droplets present in the fuel gets evaporated and hence prevents the cavitation.

10. In gear type fuel pumps bypass action is due to spill valve.

a) True

b) False

Answer: a

Explanation: In gear type fuel pump the bypass action is carried out by spill valve.

This set of Steam and Gas Turbines Multiple Choice Questions & Answers  focuses on “Elementary Gas Dynamics”.

1. Continuous flow of fluid is called as _______

a) Continuum

b) Invincible flow

c) Continuum & Invincible flow

d) None of the mentioned

Answer: a

Explanation: Continuous flow of fluid is called continuum.

2. Knudsen number does not have any __________

a) units & dimension

b) units

c) dimension

d) none of the mentioned

Answer: c

Explanation: Knudsen number does not have any dimension and units.

3. Continuum in fluids is predicted by using ________

a) Knudsen number

b) Mach number

c) Knudsen & Mach number

d) None of the mentioned

Answer:a

Explanation: Continuum in fluids is predicted by using Knudsen number. Mach number is used to define the speed of sound proportionality.

4. Ratio of mean free path to characteristic length is called as _________

a) Mach number

b) Knudsen number

c) Nusselt number

d) None of the mentioned

Answer: b

Explanation: Ratio of mean free path to characteristic length is called Knudsen number. Nusselt number is used in heat transfer.

5. Distance traveled by the molecule in between successive collisions is called as __________

a) mean free path

b) kinetic path

c) mean free path & kinetic path

d) none of the mentioned

Answer: a

Explanation: Distance traveled by the molecule in between successive collisions is called as mean free path.

6. Knudsen number is less than _______

a) 1

b) 0.5

c) 0.3

d) none of the mentioned

Answer: c

Explanation: Knudsen number is in between 0 and 0.3.

7. Continuum equations are valid only when Knudsen number is ________ than 0.3.

a) greater

b) less

c) equal

d) none of the mentioned

Answer: b

Explanation: Continuum equations are valid only when Knudsen number is less than 0.3

8. When altitude of earth is in between 90 km and 150 km Knudsen number can be in between 0.3 and _________

a) 1

b) 2

c) 3

d) 4

Answer: a

Explanation: When altitude of earth is in between 90 km and 150 km Knudsen number can be in between 0.3 and 1.

9. Knudsen number ranges in between 0.3 and 1 in ________

a) boundary & transient region

b) boundary region

c) transient region

d) none of the mentioned

Answer: c

Explanation: Knudsen number ranges in between 0.3 and 1 in transient region.

10. Kinetic theory of gasses are applicable only when Knudsen number is greater than 1.

a) True

b) False

Answer: a

Explanation: Kinetic theory of gasses are applicable when Knudsen number is greater than 1.

This set of Steam and Gas Turbines Problems focuses on “Elementary Airfoil Theory”.

1. Airfoil when passed through fluids produces ______________

a) thrust

b) drag

c) thrust & drag

d) none of the mentioned

Answer: a

Explanation: Air foil when passed through fluids produces aerodynamic forces. Thrust and Drag forces are called as aerodynamic force.

2. In subsonic flight air foil has a shape of round at the leading edge.

a) True

b) False

Answer: a

Explanation: In subsonic flight air foil has a shape of round at the leading edge.

3. Air foils when designed to work in water are called as _________

a) Dynamic air foil

b) Hydro foil

c) Dynamic air foil & Hydro foil

d) None of the mentioned

Answer: b

Explanation: Air foils when designed to work in water are called as hydro foils. Hydro is word used to describe water.

4. In air foil lift is __________ proportional to angle of attack.

a) inversly

b) not related

c) directly

d) none of the mentioned

Answer: c

Explanation: In air foil lift is directly proportional to angle of attack. If angle of attack is increased its lift is increased.

5. Cambered air foils generate lift at ________ angle of attack.

a) zero

b) high

c) low

d) none of the mentioned

Answer: a

Explanation: Cambered air foils generate lift at zero angle of attack. While other type of air foils require some minimum angle of attack to produce lift.

6. _________ difference is observed in between the sides of air foil.

a) Temperature

b) Pressure

c) Temperature & pressure

d) None of the mentioned

Answer: b

Explanation: Pressure difference is observed in between the sides of air foil. Due to fluid lines difference in both sides of the airfoil pressure difference is established.

7. Relation between angle of attack and _______ for invincible fluids is found in thin airfoil theory.

a) Lift

b) Drag

c) Lift & Drag

d) None of the mentioned

Answer: a

Explanation: Relation between angle of attack and lift for invincible fluids is found in thin airfoil theory.

8. Slope between lift coefficient and angle of attack in a line is __________

a) 90 degree

b) 180 degree

c) 360 degree

d) 60 degree

Answer: c

Explanation: Slope between lift coefficient and angle of attack in a line is 360 degrees.

9. Center of pressure lies exactly in ________ of the chord from the leading edge in a symmetrical air foil.

a) one quarter

b) half

c) three fourth

d) none of the mentioned

Answer: a

Explanation: Center of pressure lies exactly in one quarter of the chord from the leading edge in a symmetrical air foil.

10. Aerodynamic center lies exactly at ______ on the chord from leading edge in cambered air foil.

a) half

b) one quarter

c) three fourth

d) none of the mentioned

Answer: b

Explanation: Aerodynamic center lies exactly at one quarter on the chord from leading edge in cambered air foil.

This set of Steam and Gas Turbines Multiple Choice Questions & Answers  focuses on “Usage of Cryogenics in Gas Turbines”.

1. In cryogenic rocket engines use oxidizer as fuel.

a) True

b) False

Answer: a

Explanation: In cryogenic rocket engines use oxidizer as fuel.

2. Cryogenic fuels are stored under _______ temperatures.

a) high

b) low

c) medium

d) none of the mentioned

Answer: b

Explanation: Cryogenic rocket fuels are stored under low temperatures. Cryogenics works under minus degree Celsius and hence they are stored in low temperatures.

3. Rocket engines require _______ mass flow rate.

a) high

b) low

c) medium

d) none of the mentioned

Answer: a

Explanation: Rocket engines require high mass flow rate. Rocket engines requires high thrust and for producing high thrust high mass flow rate is required.

4. Rocket fuels has ________ molecular weight.

a) medium

b) high

c) low

d) none of the mentioned

Answer: c

Explanation: Rocket fuels has low molecular weight.

5. Cryogenic fuels are in _________ state at room temperature and pressure.

a) gaseous

b) liquid

c) solid

d) none of the mentioned

Answer: a

Explanation: Cryogenic fuels are in a gaseous state at room temperature and pressure. Cryogenics work under low temperatures and when temperature is changed to room temperature then phase transfer takes place.

6. Cryogenic rocket engines are also called as hybrid rocket engines.

a) True

b) False

Answer: a

Explanation: Cryogenic rocket engines are also called as hybrid rocket engines.

7. Hybrid rocket engines are also called as ________ propellant rocket engines.

a) solid

b) liquid

c) solid & liquid

d) none of the mentioned

Answer: b

Explanation: Hybrid rocket engines are also called as liquid propellant rocket engines. Because fuels used in hybrid engines are in liquid state.

8. ____________ is used as cryogenic fuel.

a) Liquid oxygen

b) Liquid hydrogen

c) Combination of liquid oxygen and liquid hydrogen

d) None of the mentioned

Answer: a

Explanation: Combination of both liquid oxygen and liquid hydrogen are used as cryogenic fuel. Mixture of this liquid oxygen and liquid hydrogen results in low temperature which is a main property of cryogenic fuels.

9. Liquid hydrogen and oxygen mixture produces thrust upto ________

a) 5 Km/s

b) 4 Km/s

c) 4.5 Km/s

d) 5.5 Km/s

Answer: c

Explanation: Liquid hydrogen and oxygen mixture produces thrust upto 4.5 Km/s. Cryogenic fuels produce high thrust force.

10. _________ initiators are used in cryogenic rocket engines.

a) Pyrotechnic

b) Centrifugal

c) Pyrotechnic & Centrifugal

d) None of the mentioned

Answer: a

Explanation: Pyrotechnic initiators are used in cryogenic rocket engines.

This set of Steam and Gas Turbines Multiple Choice Questions & Answers  focuses on “Usage of Gas Turbines in Jet Engines”.

1. Jet engines are classified into _______ types.

a) 5

b) 4

c) 3

d) 2

Answer: a

Explanation: Jet engines are classified into five types. They are

Turboshafts

Turbo jets

Turbo props

Turbofans

Propfan.

2. Jet engines works on ______ cycle.

a) brayton

b) dual

c) dual

d) otto

Answer: d

Explanation: Jet engines works on brayton cycle. Gasoline engines works on the otto cycle.

3. __________ bypass turbo fan engines are used in sub sonic flights.

a) Medium

b) Low

c) High

d) None of the mentioned

Answer: c

Explanation: High bypass turbo fan engines are used in sub sonic flights. High bypass turbo fan engines produce more power output.

4. Jet engines works from newton’s law of motion.

a) True

b) False

Answer: a

Explanation: Jet engines works from newton’s law of motion.

5. Turbofans gives more efficiency when the speed is ______ than the mach speed.

a) greater

b) less

c) equal

d) none of the mentioned

Answer: b

Explanation: Turbofans efficiency decreases when the speed exceeds the mach number.

6. _________ compressors are used in turbojets.

a) Axial

b) Radial

c) Axial & Radial

d) None of the mentioned

Answer: a

Explanation: Turbojets use axial or centrifugal compressors. Centrifugal compressors pressurizes the working fluid by centrifugal principle.

7. ____________ compressors can be used in turbojets.

a) Radial

b) Centrifugal

c) Radial & Centrifugal

d) None of the mentioned

Answer: b

Explanation: Both centrifugal or axial compressors can be used in turbo jets.

8. Internal energy in the fuel is converted into __________ of the exhaust in turbojets.

a) kinetic energy

b) pressure energy

c) kinetic & pressure energy

d) none of the mentioned

Answer: a

Explanation: Internal energy in the fuel is converted into kinetic energy of the exhaust in turbojets. Compressors convert internal energy of the fluid into velocity and hence kinetic energy is increased.

9. Gas generator core is used in turbo fans.

a) True

b) False

Answer: a

Explanation: Gas generator cores are used to convert internal energy of the gas to kinetic energy of the exhaust.

10. Jet engines have ________ shafts.

a) single

b) multiple

c) single or multiple

d) none of the mentioned

Answer: c

Explanation: Jet engines may have multiple shafts depending on their energy requirements.

This set of Advanced Gas Turbines Questions & Answers focuses on “Micro Gas Turbines”.

1. _________ jets produce micro gas turbines.

a) Bladon

b) Turbo

c) Bladon & Turbo

d) None of the mentioned

Answer: a

Explanation: Bladon jets produce micro gas turbines. Due to the weight to size constraint these are used.

2. Hybrid electric vehicles are powered by _________

a) turbo shafts

b) micro gas turbines

c) turbo jets

d) none of the mentioned

Answer: b

Explanation: Hybrid electric vehicles are powered by micro gas turbines. Micro gas turbines are used by considering weight to size ratio.

3. Micro turbines are based on _________

a) weight

b) size

c) micro combustion

d) none of the mentioned

Answer: c

Explanation: Micro combustion is the basic principle micro turbines are based upon.

4. In micro turbines generator is integrated with _________

a) turbine shaft

b) combustor

c) turbine shaft & combustor

d) none of the mentioned

Answer: a

Explanation: In micro turbines generator is integrated with turbine shaft.

5. Micro turbines have ________ power to weight ratio.

a) constant

b) low

c) high

d) none of the mentioned

Answer: c

Explanation: Micro turbines have high power to weight ratio. As the weight of the micro gas turbines is less it automatically increases the ratio.

6. Micro turbines have ________ emissions.

a) high

b) low

c) medium

d) none of the mentioned

Answer: b

Explanation: Micro turbines have low emissions. As power to weight ratio is less for micro turbines emissions are also reduced in micro gas turbines.

7. Micro turbines are more efficient at ________ power level when compared to reciprocating engines.

a) high

b) low

c) medium

d) none of the mentioned

Answer: b

Explanation: Micro turbines are more efficient at low power levels when compared to reciprocating engines. As the size of micro gas turbines is less the total power produced is also less when compared to reciprocating engines.

8. Micro turbines use _______ bearings.

a) air & journal

b) journal

c) air

d) none of the mentioned

Answer:c

Explanation: Micro turbines use air bearings. As journal bearings are huge in size when compared to air bearings and weight of air bearings is also less.

9. Micro turbines can also use magnetic bearings.

a) True

b) False

Answer: a

Explanation: High temperatures and high speed of micro turbines make usage of ball bearings impractical and so micro turbines can be used with air bearings or magnetic bearings.

10. Throttling of the fuel in gas turbines is impractical.

a) True

b) False

Answer: a

Explanation: Battery is used as a buffer in micro turbines for storing electricity and hence throttling is not required in micro turbines.

This set of Steam and Gas Turbines Multiple Choice Questions & Answers  focuses on “Fuel Systems in Gas Turbines”.

1. ________ produced can be varied by varying fuel flow.

a) Exhaust gases

b) Thrust

c) Exhaust gases & Thrust

d) None of the mentioned

Answer: c

Explanation: Thrust produced can be varied by varying fuel flow. If more amount of fuel is made to flow inside more mount of energy is produced and more amount of exhaust gases are released.

2. Thrust produced also depends upon rotor _________

a) blade surface

b) blade pitch

c) blade angle

d) none of the mentioned

Answer: b

Explanation: In helicopters thrust produced is varied by varying rotor blade pitch. If the pitch of the rotor blade is increased more thrust is produced.

3. Extra fuel supply causes compressor to _______

a) stall

b) surge

c) surge & stall

d) none of the mentioned

Answer: a

Explanation: When extra fuel is supplied limiting temperature is crossed and causes compressor stall. Compressor stall is disruption of the air flow in the compressor.

4. _______ is caused when extra fuel is supplied.

a) Surge

b) Stall

c) Surge & Stall

d) None of the mentioned

Answer: c

Explanation: Surge is caused when extra fuel is supplied. Stall is also caused when extra fuel is supplied. Surge is operational limit of compressor at which minimum limits are reached.

5. When fuel flow is _______ it causes surge.

a) fuel flow is not related to surge

b) decreased

c) increased

d) none of the mentioned

Answer: c

Explanation: When fuel flow is increased it causes surge. Surge is the operational limit of compressor at which minimum levels are reached.

6. Fuel control is present in turbofan engines.

a) True

b) False

Answer: a

Explanation: Fuel control is present in turbofan engines.

7. _______ control is present in turbojets.

a) Fuel

b) Thrust

c) Fuel & Thrust

d) None of the mentioned

Answer: d

Explanation: Fuel control is present in turbojets. If the fuel is controlled it indirectly controls the thrust produced.

8. Turboprops have ________ control unit.

a) thrust

b) fuel

c) surge

d) none of the mentioned

Answer: b

Explanation: Fuel control unit is present in turboprop. By using fuel control unit amount of thrust produced can be regulated.

9. _________ control unit is present in turboshaft engines.

a) exhaust

b) fuel

c) thrust

d) none of the mentioned

Answer:b

Explanation: Fuel control unit is present in turboshaft engines. Thrust is varied by using fuel control unit in turboshaft engines.

10. Variable displacement pump is present in fuel control units.

a) True

b) False

Answer: a

Explanation: Variable displacement pumps have variable displacements which was used to meet the fuel requirements.

This set of Steam and Gas Turbines Multiple Choice Questions & Answers  focuses on “Bearing System in Gas Turbines”.

1. Journal bearings are used to give ______ support.

a) radial

b) axial

c) radial & axial

d) none of the mentioned

Answer: a

Explanation: Radial support is given by using journal bearing. Axis of the bearings keeps on changing with the rotation.

2. _________ positioning is given by thrust bearings.

a) Axial

b) Radial & axial

c) Radial

d) None of the mentioned

Answer: c

Explanation: Thrust bearings is used to give axial positioning. Thrust bearings provide supporting reaction to the bearings in axial direction.

3. ________ bearings are used in aircraft engines.

a) Roller

b) Axial

c) Radial

d) All of the mentioned

Answer: d

Explanation: Roller bearings are used in aircraft engines. Each bearing is used in its respective place where its presence is required.

4. Ball bearings are used in aircraft engines.

a) True

b) False

Answer: a

Explanation: Ball bearings are used in aircraft engines.

5. ____________ bearings are used in all industrial turbines.

a) Roller

b) Ball

c) Journal

d) None of the mentioned

Answer: c

Explanation: Journal bearings are used in all industrial turbines. Roller and Ball bearings are used in air craft engines.

6. Journal bearings are _________ sized.

a) square

b) round

c) large

d) none of the mentioned

Answer: b

Explanation: Journal bearings can be either split or round sized. No bearing is present in square sized and all bearings are small in size.

7. Journal bearings can be ________ sized.

a) round

b) split

c) round & split

d) none of the mentioned

Answer: c

Explanation: Journal bearings can be split or round sized. The selection of size either round or split is selected based on the forces acting and the use of the bearing at that respective place.

8. Precision insert type bearings have _______ lining.

a) thin

b) thick

c) small

d) none of the mentioned

Answer: a

Explanation: Precision insert type bearings have thin lining and are used in the internal combustion engine.

9. Sleeve bearings are commonly _________ type.

a) split

b) round

c) journal

d) none of the mentioned

Answer: a

Explanation: Sleeve bearings are commonly split type. Sleeve bearings are used in sleeves and split type is required in that place.

10. Cylindrical _______ bearing has split design.

a) roller

b) bore

c) journal

d) none of the mentioned

Answer: b

Explanation: Cylindrical bore bearing has split design. Round bearings increase the point of contact and increases the energy losses.

This set of Steam and Gas Turbines Multiple Choice Questions & Answers  focuses on “Combustion System in Gas Turbines”.

1. After burners are used to ________ the thrust.

a) increase

b) decrease

c) afterburners are not related to thrust

d) none of the mentioned

Answer: a

Explanation: After burners are used to increase the thrust. After burners collect the exhaust gases from exhaust frame and reheat them and uses the remaining kinetic energy of the gases and increases the thrust produced.

2. Extra fuel is injected to afterburners to _________ the thrust.

a) decrease

b) increase

c) extra fuel is not injected

d) none of the mentioned

Answer: b

Explanation: Extra fuel is injected to afterburners to increase the thrust. All the exhaust gases from exhaust frame is brought into afterburners and burned again with the help of extra fuel added into afterburner.

3. Afterburners consume _______ fuel amounts.

a) medium

b) low

c) high

d) none of the mentioned

Answer: c

Explanation: Afterburners consume high fuel amounts. For exhaust gases left after combustion from combustion chamber extra amount of fuel is added to the afterburner to burn again so that the remaining traces of fuel in exhaust gases get burned.

4. By using afterburners efficiency is _________

a) increased

b) decreased

c) not effected

d) none of the mentioned

Answer: b

Explanation: By using afterburners efficiency is decreased. As more amount of fuel is required in after burners.

5. When jet engines use afterburners engines are ________

a) wet

b) dry

c) semi dry

d) none of the mentioned

Answer: a

Explanation: When jet engines use afterburners engines are wet. For working of afterburners a continuous supply of fuel need to be given and hence they are wet.

6. When afterburners are not used in jet engines they are ________

a) wet

b) dry

c) semi dry

d) none of the mentioned

Answer: b

Explanation: When afterburners are not used in jet engines they are dry. Exhaust gases are dry which makes jet engine dry.

7. Afterburners are not equipped with case and liners.

a) True

b) False

Answer: b

Explanation: After burners are equipped with both case and liners.

8. Afterburners have _______ rise in temperature than combustors.

a) low

b) equal

c) high

d) none of the mentioned

Answer: c

Explanation: Afterburners have high rise in temperature when compared to combustors. As already the exhaust gases are present in high temperatures and when again burned by adding some fuel the exhaust gases that are released from afterburners that have high temperatures.

9. Mixing of fuel takes place efficiently in afterburners.

a) True

b) False

Answer: b

Explanation: Mixing of fuel is not that efficient in afterburners.

10. Afterburners require _________

a) flame holder

b) nozzle

c) casing

d) none of the mentioned

Answer: a

Explanation: Flame holders are used to maintain a constant velocity of flame. If the flame in afterburners are produced with different velocities combustion of the flame may not be constant.

This set of Steam and Gas Turbines Multiple Choice Questions & Answers  focuses on “Turbine Casting and Exhaust Frames”.

1. Exhaust frame and exhaust diffuser are connected ____________

a) one after other

b) together

c) not connected

d) none of the mentioned

Answer: b

Explanation: Exhaust frame and exhaust diffuser are connected together. Gases coming out of exhaust frames has high pressure and when connected to diffuser pressure energy is converted into velocity.

2. Exhaust frame is connected to the _________

a) aft flange

b) diffuser

c) aft flange & diffuser

d) none of the mentioned

Answer:c

Explanation: Exhaust frame is connected to the aft flange and also diffuser. Exhaust frame is connected to diffuser using aft flange.

3. Aft flange is present on the turbine shell.

a) True

b) False

Answer: a

Explanation: Aft flange is present on the turbine shell.

4. _____________ are further divided in outer cylinder and inner cylinder.

a) Aft flange & Exhaust frame

b) Aft flange

c) Exhaust frame

d) None of the mentioned

Answer: c

Explanation: Exhaust frames are further divided in outer cylinder and inner cylinder. Inner cylinder of exhaust frame has parts used to connect to diffuser.

5. In exhaust frames inner and outer cylinder are connected using __________

a) structs

b) aft flange

c) structs & aft flange

d) none of the mentioned

Answer: a

Explanation: Structs are used to connect both inner and outer cylinder in exhaust frame. Where as aft flange is connected to outer casing of the exhaust frame.

6. Exhaust diffuser is located at extreme _________

a) aft flange

b) aft end

c) exhaust frame

d) none of the mentioned

Answer: b

Explanation: Exhaust diffuser is located at extreme aft end. Where one end of aft flange is connected to exhaust frame.

7. Exhaust diffuser is supported by exhaust frame.

a) True

b) False

Answer: a

Explanation: Exhaust diffuser is supported by exhaust frame.

8. __________ are present at the end of exhaust diffuser.

a) Guide vanes

b) Stationary vanes

c) Guide & Stationary vanes

d) None of the mentioned

Answer: c

Explanation: Guide vanes are present at the end of exhaust diffuser. Stationary vanes are used to guide the working fluid in the required direction and hence they are also called as guide vanes.

9. Struts supporting inner and outer cylinder are to be maintaned at _______ temperature.

a) increasing

b) variable

c) constant

d) none of the mentioned

Answer: c

Explanation: When temperature is not constant thermal stresses developed and center position may vary.

Answer: a

Explanation: Cooling air is made to flow so that the temperature remains constant.

This set of Steam and Gas Turbines Multiple Choice Questions & Answers  focuses on “Compressor Parts of Gas Turbines”.

1. Airfoils are present in the ________ of the compressor.

a) inlet

b) outlet

c) middle

d) none of the mentioned

Answer: a

Explanation: Airfoils are used to produce swirl motion in the inlet. Hence they are present in the inlet.

2. Valve’s are present in the ________ of the centrifugal compressor.

a) middle

b) outlet

c) inlet

d) none of the mentioned

Answer: c

Explanation: Valve’s are present in the inlet of the centrifugal compressor. Valves are used to inject working fluids into the compressor.

3. Stationary vanes are present in the ________ of the compressor.

a) outlet

b) inlet

c) middle

d) none of the mentioned

Answer: b

Explanation: Stationary vanes are present in the inlet of the compressor. Stationary vanes help in directing the fluid into required direction.

4. Compressor belts are present in order to avoid ________ losses.

a) pressure

b) temperature

c) pressure & temperature

d) none of the mentioned

Answer: a

Explanation: Compressor belts are present to provide tight seal so that pressure loss doesn’t take place.

5. Unloader valves are used to _________ the load on the compressor.

a) increase

b) deccrease

c) unloader does not alter load

d) none of the mentioned

Answer: b

Explanation: Unloader valves are used to decrease the load on the compressor. When the compressor reaches maximum load then unloader is used.

6. Check valves are used in the compressor.

a) True

b) False

Answer: a

Explanation: Check valves are used to check whether the required pressure is maintained or not.

7. _____________ are present in the centrifugal impeller.

a) Rotating vanes

b) Stationary vanes

c) Rotating & Stationary vanes

d) None of the mentioned

Answer: c

Explanation: Rotating vanes increases the energy of the working gas. Stationary vanes are used to direct the flow of the steam.

8. Exit velocity of the gas in the centrifugal compressor is equal to __________

a) speed of sound

b) double the speed of sound

c) half the speed of sound

d) none of the mentioned

Answer: a

Explanation: Exit velocity of the gas in the centrifugal compressor is equal to speed of the sound. Outlet pressure is very high in the compressor.

9. In compressor diffuser is used to convert ___________ of the gas into the velocity.

a) potential energy

b) kinetic energy

c) potential & kinetic energy

d) none of the mentioned

Answer: b

Explanation: Diffuser converts kinetic energy of the gas into velocity. In diffuser pressure is reduced which leads to increase in velocity.

10. Bernoulli’s principle is used in determining the performance of diffuser.

a) True

b) False

Answer: a

Explanation: Performance of diffuser can be determined by using bernoulli’s theorem.

This set of Gas Turbines online quiz focuses on “Inlet and Compressor Casing”.

1. Capacity of rotary screw compressor is _______ by using unloader.

a) constant

b) varied

c) unloader is not used for compressing

d) none of the mentioned

Answer: a

Explanation: Capacity of rotary screw compressor can be varied by using unloader. When unloader is completely opened its capacity gets decreased to the minimum.

2. Amount of air that can be sucked in by compressor is regulated by using ___________

a) check valve

b) feed valve

c) unloader

d) none of the mentioned

Answer: c

Explanation: Amount of air that can be sucked in can be regulated using unloader. When unloader is completely opened compressor totally minimizes the air entering the compressor.

3. Unloader is also called as intake valve.

a) True

b) False

Answer: b

Explanation: Intake valve is used to regulate the flow capacity where as unloader is used to vary the load.

4. Unloader closes 100% of the air intake.

a) True

b) False

Answer: b

Explanation: Unloader closes the intake to the maximum extent but 100% cannot be closed.

5. When unloader is closed it uses _________ work.

a) 30%

b) 50%

c) 20%

d) 40%

Answer: a

Explanation: When unloader is closed it used 30% work. For unloader to close it needs to apply some pressure which is applied in the form of work.

6. ___________ unloader are used in stationary compressors.

a) Continuous

b) Variable

c) Continuous & Variable

d) None of the mentioned

Answer: a

Explanation: Stationary compressors use continuous unloader. In stationary compressors inlet air should be frequently controlled for proper working and hence continuous unloaders are used.

7. Continuous unloader is used in _________ engine compressor.

a) diesel

b) gasoline

c) dual

d) none of the mentioned

Answer: a

Explanation: Continuous unloader is used in diesel engine compressor. In diesel engine the amount of fuel intake is to be controlled regularly.

8. When choke points are joined in graph representing speeds it is called as ________

a) temperature line

b) choke line

c) critical line

d) none of the mentioned

Answer: b

Explanation: When choke points are joined in graph representing speeds it is called as choke lines. Choke points are the points at which the turbine starts choking at that particular speed and fuel intake.

9. When compressor operates at ________ choking takes place.

a) high mass

b) low mass

c) high temperature

d) none of the mentioned

Answer: a

Explanation: When compressor operates at high mass choking takes place. When mass increases its inlet quantity increases and hence turbine starts to choke.

10. Choking occurs when mach number reaches ________

a) 3

b) 2

c) 1

d) 4

Answer: c

Explanation: When mach number reaches unity no more mass can be reached and hence choking takes place. When mach number reaches unity its speed is heavily increased and hence mass flow is also increased to a great extent.

This set of Basic Gas Turbines Interview questions and answers focuses on “Fuels Used in Gas Turbines”.

1. _______ can be used as fuels in gas turbines.

a) Natural gases

b) petroleum

c) Diesel

d) All of the mentioned

Answer: d

Explanation: Natural gases,petrol,diesel etc can be used as fuels in gas turbines. Gas turbines requires liquids with high specific heat as fuels.

2. Vanadium content in the fuels used for gas turbines should be ________

a) high

b) low

c) zero

d) none of the mentioned

Answer: b

Explanation: Vanadium content must be low in the fuels used for gas turbines. Excessive vanadium content in the fuel leads to decrease in the specific heat of the fuel.

3. Fuels used in gas turbines should have _____ ash content.

a) low

b) high

c) zero

d) none of the mentioned

Answer: a

Explanation: Fuels used in gas turbines should have low ash content. When ash content is more calorific value of fuel gets decreased.

4. Gas turbine fuels congeal at __________ degrees are used in Locomotives.

a) -20

b) -10

c) -5

d) -15

Answer: c

Explanation: Gas turbine fuels congeal at -5 degrees are used in locomotives. Congealing temperature is the temperature at which the fuel freezes.

5. Fuels that congeal at ____________ degrees are used in automobiles.

a) -12

b) -15

c) -20

d) -15

Answer: a

Explanation: Fuels that congeal at -12 degrees are used in automobiles. Fuels used in gas turbines in automobiles has a freezing point of -12 degrees.

6. ______ oil can also be used to operate gas turbine power plants.

a) Leaded

b) Non leaded

c) Crude fuel

d) None of the mentioned

Answer:c

Explanation: Crude fuel oil can also be used to operate gas turbine power plants. Crude oil is the unrefined petroleum.

7. Water soluble salts are also removed from the fuels used in gas turbines.

a) True

b) False

Answer: a

Explanation: Water soluble salts are also removed from the fuels used in gas turbines. If the salts are not removed there is a chance for surge formation.

8. lead content must be ______ in gas turbine fuels.

a) high

b) low

c) zero

d) none the mentioned

Answer: b

Explanation: Lead content must be low in gas turbine fuels. If the lead content is increased it decreases the calorific value of the fuel.

9. Power loss will be _____ if impurities are present in gas turbine.

a) zero

b) less

c) high

d) none of the mentioned

Answer: c

Explanation: If impurities are present in fuel it consumes much heat to start combustion and hence power loss takes place.

10. Inhibitors are added to attack the ash developed by combustion of vanadium in gas turbine fuels.

a) True

b) False

Answer: a

Explanation: Inhibitors are added to attack the ash developed by combustion of vanadium in gas turbine fuels. Inhibitors reacts with vanadium and make them easy combustible during combustion.

This set of Steam and Gas Turbines Multiple Choice Questions & Answers  focuses on “Working of a Steam Turbines”.

1. _______ of electricity in United States is produced using steam turbine.

a) 88%

b) 50%

c) 100%

d) 77%

Answer: a

Explanation: 88% of electricity in United States is produced using steam turbine. US is one among the few countries that depends mostly on the steam turbine power plants.

2. When steam pressure ________ it becomes superficial fluid.

a) Decreases

b) Increases

c) Steam can not become superficial fluid

d) None of the mentioned

Answer: b

Explanation: When steam pressure increases it becomes superficial fluid. When pressure increases its temperature also gets increased then it changes into superficial fluid.

3. Steam turbines used in nuclear reactors use __________

a) Superficial fluids

b) High pressure steam

c) Specific heat

d) None of the mentioned

Answer: a

Explanation: Steam turbines used in nuclear reactors use superficial fluids. High pressure steam is also called as superficial fluid. Steam used in nuclear reactors need to have high kinetic energy where kinetic energy in superficial fluid is sufficient for nuclear reactor.

4. ________ and pressure of the superficial steam are at critical points.

a) Specific heat

b) Volume

c) Temperature

d) None of the mentioned

Answer: c

Explanation: Temperature and pressure of the superficial steam are at critical points. Critical point is the point at which steam changes its phase.

5. Superficial steam power plants operate at _____ temperatures.

a) high

b) low

c) constant

d) none of the mentioned

Answer: a

Explanation: Superficial steam power plants operate at high temperatures. Superficial steam has high pressure which means for steam to get into superficial state high temperature is required.

6. Energy efficiency of superficial steam is _________

a) low

b) high

c) same as other steams

d) none of the mentioned

Answer: b

Explanation: Energy efficiency of superficial steam is very high. As temperature of superficial steam is very high it leads to high energy efficiency.

7. Superficial steam turbines can be operated at ________

a) medium speeds

b) low speeds

c) high speeds

d) none of the mentioned

Answer: c

Explanation: Superficial steam turbines can be operated at high speeds. Because it produces high heat energy which can be converted into rotational energy.

8. Superficial steam turbines releases _______ CO 2 .

a) high

b) low

c) does not release

d) none of the mentioned

Answer: a

Explanation: Superficial steam turbine releases less pollutants. Because there will be less wastage of heat and hence pollutants are controlled.

9. In double acting steam engine pressure acts on the both sides of the valves.

a) True

b) False

Answer: a

Explanation: In double acting steam engine pressure acts on the both sides of the valves. That is why those steam engines are called as double acting steam engines.

10. Boiler extracts heat from the working fluid.

a) True

b) False

Answer: a

Explanation: Boiler extracts the amount of heat from the working fluid. When fluid is boiled inside the boiler it releases the heat energy.

This set of Steam and Gas Turbines Multiple Choice Questions & Answers  focuses on “Fire Resisting Fluids in Steam Turbines”.

1. Fire resistant fluids can be used in __________ pressures.

a) high

b) low

c) both high and low

d) none of the mentioned

Answer: c

Explanation: Fire resistant fluids can be used in high and also low pressure. But mostly fire resistant fluids are used under high pressures as they don’t have any use in the case of low pressures.

2. __________ esters can be used as fire resistant fluids.

a) Phosphate

b) Potassium

c) Sodium

d) None of the mentioned

Answer: a

Explanation: Phosphate esters can be used as fire resistant fluids. As boiling point of phosphate esters are high they can withstand to high temperatures without boiling.

3. Ester mineral blends can also be used as fire resistant fluids.

a) True

b) False

Answer: a

Explanation: Ester mineral blends can also be used as fire resistant fluids. As esters have high boiling points.

4. _______ glycols can also be used as fire resistant fluids.

a) Methylene

b) Ethylene

c) Water

d) None of the mentioned

Answer: c

Explanation: Water glycols can also be used as fire resistant fluids. Water when mixed with glycols their boiling point gets increased and hence these can be used as fire resisting fluids.

5. Fire resistance is _________ proportional to smoothening of the steam.

a) inversly

b) directly

c) fire resistance is not related to steam smootheness

d) none of the mentioned

Answer: b

Explanation: Fire resistance is directly proportional to smoothening of the steam. When there is no fire resistance there will be vigorous combustion taking place which will lead to improper production of steam.

6. Fire resistance of fluids is _______ to the vaporization of the fluid.

a) inversely proportional

b) directly proportional

c) both are no where related

d) None of the mentioned

Answer: a

Explanation: Fire resistance of fluids is proportional to the vaporization of the fluid. If the fluid is highly vaporizable then its fire resistance decreases as fluid gets easily vaporized at low temperatures.

7. __________ is the important feature of the fire resistant fluid.

a) Specific volume

b) Specific heat

c) Viscosity

d) None of the mentioned

Answer: c

Explanation: Viscosity is the important feature of the fire resistant fluid. If the fluid has high viscosity it does not get combusted easily.

8. Fire resistant fluids are selected based on operating ____________

a) temperature

b) pressure

c) temperature & pressure

d) none of the mentioned

Answer: c

Explanation: Fire resistant fluids are selected based on both operating pressure and temperature as pressure is directly proportional to temperature when the volume is constant. Temperature is considered because the fluid that is selected must be able to withstand the working temperature without getting vaporized.

9. ___________ resistance is taken into the consideration while selecting fire resistant fluid.

a) Corrosion

b) Frictional

c) Corrosion & Frictional

d) None of the mentioned

Answer: a

Explanation: Corrosion resistance is taken into the consideration while selecting fire resistant fluid. If the fluid is less corrosion resistant the combustion chambers get corroded easily which leads to break down of the gas turbine.

10. Heat resistant fluids are in _______ color.

a) Black

b) White

c) Colorless

d) None of the mentioned

Answer: b

Explanation: Heat resistant fluids are either red or pink dye color. The quality of the heat resistance offered by the fluid can be determined by the darkness of the color.

This set of Steam and Gas Turbines Multiple Choice Questions & Answers  focuses on “Hydrogen Seal Rings in Turbine Generator”.

1. Hydrogen seal rings are used to prevent _______ losses.

a) Pressure

b) Temperature

c) Volume

d) None of the mentioned

Answer: a

Explanation: Hydrogen seal rings are used to prevent pressure losses. These rings seal the cylinders so that no pressure and temperature loss takes place.

2. _________ oil flow can be controlled by using hydrogen rings.

a) Low

b) Excessive

c) Incomplete

d) None of the mentioned

Answer: b

Explanation: Hydrogen rings control excessive oil flow.Excessive oil flow consumes more heat and increases the heat loss.

3. Hydrogen rings are used to control _______ consumption in gas turbine.

a) Fuel

b) Oxygen

c) Hydrogen

d) None of the mentioned

Answer: c

Explanation: Hydrogen rings are used to control hydrogen consumption in gas turbine. Hydrogen is used as coolant in gas turbine, Excessive usage of coolant leads to low efficiency.

4. When hydrogen consumption is __________ its efficiency is decreased in turbo generators.

a) increased

b) decreased

c) constant

d) none of the mentioned

Answer: a

Explanation: Hydrogen consumption is inversely proportional to efficiency in turbo generators. As hydrogen is used as the coolant and when more amount of coolant is used most heat is lost and hence efficiency is decreased.

5. _________ is used as coolant in turbo generators.

a) Oxygen

b) Hydrogen

c) Fuel

d) None of the mentioned

Answer: b

Explanation: Hydrogen is used as coolant in turbo generators. Compared to the other coolants available for gas turbines hydrogen is much cheaper.

6. Hydrogen is combustible below _______% purity limit.

a) 74

b) 50

c) 100

d) 120

Answer: a

Explanation: Hydrogen is combustible below 74% purity limit.

7. Hydrogen rings are made at _____ degree segments.

a) 360

b) 90

c) 180

d) 60

Answer: c

Explanation: Hydrogen rings are made at 180 degree segments. The total ring circumference must be 360 degree comprising two parts  each of 180 degree.

8. Hydrogen rings are of two parts upper case and lower case.

a) True

b) False

Answer: a

Explanation: Hydrogen rings are of two parts upper case and lower case.

9. Hydrogen is used because of its ______ specific heat.

a) high

b) low

c) specific is not the factor considered while selecting

d) none of the mentioned

Answer: b

Explanation: Hydrogen is used because of its low specific heat.

10. For hydrogen to use as coolant its purity must be more than _______

a) 74%

b) 50%

c) 100%

d) 40%

Answer: a

Explanation: For hydrogen to use as coolant its purity must be more than 74%. Below 74% hydrogen is more combustible in nature.

This set of Steam and Gas Turbines Multiple Choice Questions & Answers  focuses on “Steam Turbine Cylinders”.

1. Pressure acting on the turbine cylinders is _______

a) low

b) high

c) depending on the volume

d) none of the mentioned

Answer: b

Explanation: Pressure acting on the turbine cylinders is very high due to high temperatures.

2. _________ stresses are developed on the wall of cylinder in steam turbine.

a) Compressive

b) Static

c) Thermal

d) None of the mentioned

Answer: c

Explanation: Thermal stresses are developed on the wall of cylinder in steam turbine as high temperatures and high pressures are acting.

3. Thickness of the cylinder wall must be ________ in steam turbines.

a) constant

b) increased

c) decreasing

d) none of the mentioned

Answer: a

Explanation: Thickness of the cylinder wall must be maintained constant in steam turbines because if the thickness is uneven there will be uneven thermal stresses developed.

4. Steam entering cylinder has ______ temperature than the steam present in the cylinder.

a) less

b) more

c) equal

d) none of the mentioned

Answer: b

Explanation: Steam entering cylinder has more temperature than the steam present in the cylinder as the heat energy from the steam inside the cylinder will be used up.

5. ________ cylinder is used in steam turbine.

a) One

b) Multiple

c) Either one or multiple depending on the requirement

d) None of the mentioned

Answer: c

Explanation: More than one cylinder are joined together to make steam turbine generator to work.The number of cylinders that are to be used is specified based on the volume required.

6. All the cylinders used in steam turbine are worked under _______ pressure.

a) same

b) increasing pressure

c) decreasing pressure

d) none of the mentioned

Answer: b

Explanation: Pressure in the steam turbine cylinders is not constant it varies from cylinder to cylinder.The pressure in each cylinder is varied so that pressure compounding can be attained.

7. Pressures of the cylinders in steam turbines are arranged according to the specific _______

a) temperature

b) pressure

c) volume

d) none of the mentioned

Answer: c

Explanation: As steam moves from one cylinder to another cylinder its pressure keeps on decreasing and specific volume keeps increasing. Hence cylinders are arranged according to the increase of the specific volume of the working fluid.

8. _______ can also be done to the steam in between the cylinders of steam turbine.

a) Reheating

b) Regenerating

c) Recuperating

d) None of the mentioned

Answer: a

Explanation: Reheating can also be done to the steam in between the cylinders of steam turbine so that pressure compounding will be possible.

9. Some nozzles are equipped on the ________

a) Reheating

b) Rotating shaft

c) Casing

d) Cylinders

Answer: d

Explanation: Some nozzles are equipped on the cylinders, so that intermediate reheating can be done to the working fluid and unwanted gases can be driven out.

10. ________ takes place due to thermal stresses in the steam turbine cylinder.

a) Expansion

b) Compression

c) Depends

d) None of the mentioned

Answer: a

Explanation: Expansion takes place due to thermal stresses in the steam turbine cylinder. As steam turbine cylinders are made of some metal, thermal expansion may take place.