Steam and Gas Turbines Multiple Choice Questions 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
Clarification: 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
Clarification: 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
Clarification: 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
Clarification: 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
Clarification: 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
Clarification: 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
Clarification: 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
Clarification: 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
Clarification: 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
Clarification: Performance of diffuser can be determined by using bernoulli’s theorem.