Compressors, Gas Turbines and Jet Engines MCQs

Question 1

For maximum work, the reheating should be done to an intermediate pressure of (Where p1 = Maximum pressure and p2 = Minimum pressure)

Accepted Answer

$${{	ext{p}}_1}{{	ext{p}}_2}$$

Answer

$$\frac{{{{	ext{p}}_1} - {{	ext{p}}_2}}}{2}$$

Answer

$$\frac{{{{	ext{p}}_1} + {{	ext{p}}_2}}}{2}$$

Answer

$$\frac{{{{	ext{p}}_1}}}{{{{	ext{p}}_2}}}$$

Question 2

Inter-cooling in multistage compressors is done

Accepted Answer

To minimize the work of compression

Answer

To cool the air during compression

Answer

To cool the air at delivery

Answer

To enable compression in two stages

Question 3

The efficiency and work ratio of a gas turbine plant can be increased by

Accepted Answer

All of the above

Answer

Adding heat exchanger

Answer

Injecting water in/around combustion chamber

Answer

Reheating the air after partial expansion in the turbine

Question 4

The thrust of a jet propulsion power unit can be increased by

Accepted Answer

All of the above

Answer

Injecting water into the compressor

Answer

Burning fuel after gas turbine

Answer

Injecting ammonia into the combustion chamber

Question 5

Euler's equation can be used for

Accepted Answer

All of these

Answer

Radial flow compressors

Answer

Axial flow compressors

Answer

Pumps

Question 6

Adiabatic compression is one in which

Accepted Answer

No heat leaves or enters the compressor cylinder during compression

Answer

Temperature during compression remains constant

Answer

Temperature rise follows a linear relationship

Answer

Work done is maximum

Question 7

Ratio of compression is the ratio of

Accepted Answer

Absolute discharge pressure to the absolute intake pressure

Answer

Gauge discharge pressure to the gauge intake pressure

Answer

Pressures at discharge and suction corresponding to same temperature

Answer

Stroke volume and clearance volume

Question 8

The work done per unit mass of air in compression will be least when 'n' is equal to

Accepted Answer

1

Answer

1.2

Answer

1.3

Answer

1.4

Question 9

The efficiency of roots blower ________ with the increase in pressure ratio.

Accepted Answer

Decreases

Answer

Increases

Answer

Does not change

Answer

None of these