Compressors, Gas Turbines and Jet Engines MCQs

Question 1

Separators are generally used in air compressor installations

Accepted Answer

Between the after-cooler and receiver

Answer

Before the inter-cooler

Answer

After the inter-cooler

Answer

Before first stage suction

Question 2

A 3 m3/min compressor means that it

Accepted Answer

Compresses 3 m3/min of free air

Answer

Compresses 3 m3/min of standard air

Answer

Delivers 3 m3/min of compressed air

Answer

Delivers 3 m3/min of compressed air at delivery pressure

Question 3

Clearance volume in actual reciprocating compressors is essential

Accepted Answer

To provide cushioning effect and also to avoid mechanical bang of piston with cylinder head

Answer

To accommodate Valves in the cylinder head

Answer

To provide cushioning effect

Answer

To attain high volumetric efficiency

Question 4

The pressure of air at the beginning of the compression stroke is ________ the atmospheric pressure.

Accepted Answer

Less than

Answer

Equal to

Answer

More than

Answer

None of these

Question 5

A closed gas turbine in which fuel is burnt directly in the air is not possible because of

Accepted Answer

Paucity of O2

Answer

Increasing gas temperature

Answer

High specific volume

Answer

High friction losses

Question 6

For minimum work required to compress and deliver a quantity of air by multistage compression

Accepted Answer

All of the above

Answer

The compression ratio in each stage should be same

Answer

The intercooling should be perfect

Answer

The work-done in each stage should be same

Question 7

Pick up the wrong statement about advantages of multistage compression

Accepted Answer

More loss of air due to leakage past the cylinder

Answer

Better lubrication is possible advantages of multistage

Answer

Mechanical balance is better

Answer

Air can be cooled perfectly in between

Question 8

Which is false statement about advantages of multistage compressor in comparison to single stage compressor?

Accepted Answer

Lower volumetric efficiency

Answer

Less power requirement

Answer

Better mechanical balance

Answer

Less loss of air due to leakage past the cylinder

Question 9

In an axial flow compressor, the ratio of pressure in the rotor blades to the pressure rise in the compressor in one stage is known as

Accepted Answer

Degree of reaction

Answer

Work factor

Answer

Slip factor

Answer

Pressure coefficient