Compressors, Gas Turbines And Jet Engines MCQ Questions & Answers

Compressors, Gas Turbines And Jet Engines MCQ Questions & Answers | Mechanical Engineering

Learn Compressors, Gas Turbines And Jet Engines MCQ questions & answers are available for a Mechanical Engineering students to clear GATE exams, various technical interview, competitive examination, and another entrance exam. Compressors, Gas Turbines And Jet Engines MCQ question is the important chapter for a Mechanical Engineering and GATE students. Page-2 section-1

Rotary compressors are suitable for

A) Large discharge at high pressure B) Low discharge at high pressure C) Large discharge at low pressure D) Low discharge at low pressure

Discuss

Answer & Solution

Answer: Option C

Solution:

Rotary compressors are suitable for Large discharge at low pressure

An air compressor may be controlled by

A) Throttle control B) Clearance control C) Blow off control D) Any one of the above

Discuss

Answer & Solution

Answer: Option D

Solution:

An air compressor may be controlled by
-Throttle control
- Clearance control
- Blow off control

The degree of reaction of an axial flow turbine is the ratio of isentropic temperature drop in a blade row to the

A) Adiabatic temperature drop in the stage B) Total temperature drop C) Total temperature drop in the stage D) Total adiabatic temperature drop

Discuss

Answer & Solution

Answer: Option C

Solution:

The degree of reaction of an axial flow turbine is the ratio of isentropic temperature drop in a blade row to the Total temperature drop in the stage.
The degree of reaction contributes to the stage efficiency and thus used as a design parameter. Stages having 50% degree of reaction are used where the pressure drop is equally shared by the stator and the rotor for a turbine.

The net work input required for compressor with increase in clearance volume

A) Increases B) Decreases C) Remains same D) Increases/decreases depending on compressor capacity

Discuss

Answer & Solution

Answer: Option C

Solution:

The net work input required for compressor with increase in clearance volume remains same

Volumetric efficiency of a compressor without clearance volume

A) Increases with increase in compression ratio B) Decreases with increase in compression ratio C) Is not dependent upon compression ratio D) May increase/decrease depending on compressor capacity

Discuss

Answer & Solution

Answer: Option C

Solution:

A compressor's volumetric efficiency (V) is defined by the ratio of the actual volume of gas that it could suck if there was no such thing as clearance volume.
Therefore, a compressor with less clearance volume should be more volumetrically efficient.

Volumetric efficiency of a compressor with clearance volume

A) Increases with increase in compression ratio B) Decreases with increase in compression ratio C) In not dependent upon compression ratio D) May increase/decrease depending on compressor capacity

Discuss

Answer & Solution

Answer: Option B

Solution:

Volumetric efficiency of a compressor with clearance volume Decreases with increase in compression ratio

Compression efficiency is compared against

A) Ideal compression B) Adiabatic compression C) Isentropic compression D) Isothermal compression

Discuss

Answer & Solution

Answer: Option D

Solution:

Compression efficiency is compared against Isothermal compression

Phenomenon of choking in compressor means

A) No flow of air B) Fixed mass flow rate regardless of pressure ratio C) Reducing mass flow rate with increase in pressure ratio D) Increased inclination of chord with air steam

Discuss

Answer & Solution

Answer: Option B

Solution:

Choke/Stonewall point Choking is the condition which occurs in the compressor in which it operates at very high mass flow rate and flow through the compressor can't be further increased as mach number at some part of the compressor reach to unity

Reheating in a multistage expansion gas turbine ________ compressor work.

A) Has no effect on B) Decreases C) Increases D) None of these

Discuss

Answer & Solution

Answer: Option B

Solution:

Reheating in a multistage expansion gas turbine Decreases compressor work.

The work ratio of simple gas turbine cycle depends on

A) Pressure ratio B) Maximum cycle temperature C) Minimum cycle temperature D) All of the above

Discuss

Answer & Solution

Answer: Option D

Solution:

The work ratio of simple gas turbine cycle depends on
- Pressure ratio
- Maximum cycle temperature
- Minimum cycle temperature