Gas Dynamics And Gas Turbines(Engineering > Mechanical Engineering > Compressors ) Questions and Answers
Question 1. Reheating in a gas turbine
increases the thermal efficiency
increases the compressor work
increases the turbine work
decreases the thermal efficiency
Explanation:-
Answer: Option A. -> increases the thermal efficiency Answer: (a).increases the thermal efficiency
Question 2. In a compressed air system, the temperature of air discharged from the air motor is __________ than the initial compressor intake temperature.
more
less
Can't say
None of these
Explanation:-
Answer: Option B. -> less Answer: (b).less
Question 3. In a single stage, single acting reciprocating air compressor, without clearance, the workdone on the air during isentropic compression is __________ the heat required to raise the temperature of air from T1 to T2 at a constant pressure.
equal to
less than
greater than
None of these
Explanation:-
Answer: Option A. -> equal to Answer: (a).equal to
Question 4. Workdone by an air compressor __________ upon the way in which the air is compressed.
depends
does not depend
Can't say
None of these
Explanation:-
Answer: Option A. -> depends Answer: (a).depends
Question 5. In a compressor, work is done on the piston during suction of air and work is done by the piston during compression as well as delivery of air.
Agree
Disagree
Can't say
None of these
Explanation:-
Answer: Option A. -> Agree Answer: (a).Agree
Question 6. The compressor efficiency is defined as the ratio of volume of free air delivery per stroke to the swept volume of the piston.
Correct
Incorrect
Can't say
None of these
Explanation:-
Answer: Option B. -> Incorrect Answer: (b).Incorrect
Question 7. In open cycle turbo-jet engines used in military aircraft, reheating the exhaust gas from the turbine by burning, more fuel is used to increase the
thrust and range of aircraft
efficiency of the engine
both (a) and (b)
none of these
Explanation:-
Answer: Option A. -> thrust and range of aircraft Answer: (a).thrust and range of aircraft
Question 8. Gas turbine as compared to internal combustion engine
can be driven at a very high speed
produces uniform torque
has more efficiency
all of these
Explanation:-
Answer: Option D. -> all of these Answer: (d).all of these
Question 9. In a gas turbine, air is obtained from the atmosphere and compressed in an air compressor.
True
False
Can't say
None of these
Explanation:-
Answer: Option A. -> True Answer: (a).True
Question 10. The performance of air compressor at high altitudes will be __________ as compared to that at sea level.