Category: Steam and Gas Turbines Objective Questions

Steam and Gas Turbines Questions and Answers for experienced 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
Clarification: 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
Clarification: 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
Clarification: 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
Clarification: 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
Clarification: 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
Clarification: 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
Clarification: 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
Clarification: 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
Clarification: 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
Clarification: Angle of vector drawn normal to the exit is called a reversal efflux angle.

Steam and Gas Turbines for Experienced,

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Steam and Gas Turbines Multiple Choice Questions 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
Clarification: 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
Clarification: 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
Clarification: 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
Clarification: 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
Clarification: 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
Clarification: 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
Clarification: 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
Clarification: 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
Clarification: In nozzle supersaturation causes an increase in entropy.

10. When mass flow rate is maximum nozzle chokes.
a) True
b) False
Answer: a
Clarification: Nozzle chokes when mass flow rate is maximum during critical conditions.

Steam and Gas Turbines Multiple Choice Questions 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
Clarification: 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
Clarification: 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
Clarification: 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
Clarification: 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
Clarification: 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
Clarification: 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
Clarification: 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
Clarification: 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
Clarification: 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
Clarification: When specific heat increases flame temperature increases.

Steam and Gas Turbines Problems 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
Clarification: 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
Clarification: 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
Clarification: 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
Clarification: 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
Clarification: 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
Clarification: 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
Clarification: 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
Clarification: 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
Clarification: 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
Clarification: Aerodynamic center lies exactly at one quarter on the chord from leading edge in cambered air foil.

To practice problems on all areas of Steam and Gas Turbines,

Steam and Gas Turbines Multiple Choice Questions 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
Clarification: 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
Clarification: 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
Clarification: 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
Clarification: 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
Clarification: 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
Clarification: 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
Clarification: 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
Clarification: 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
Clarification: 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
Clarification: When boiler pressure is increased steam temperature increases which increases efficiency.

Steam and Gas Turbines Multiple Choice Questions on “Introduction”.

1. Gas turbines burn fuel to run their turbines.
a) True
b) False

Answer: a
Clarification: 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
Clarification: 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
Clarification: 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
Clarification: 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
Clarification: 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
Clarification: 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
Clarification: 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
Clarification: 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
Clarification: 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
Clarification: Micro turbines are also called as turbo generators.