Power Plant Engineering (2171910) MCQs

MCQs of Gas Turbine

Showing 31 to 40 out of 52 Questions
31.

The thermal efficiency of a simple gas turbine for a given turbine inlet temperature  with an increase in pressure ratio

(a)

increases

(b)

decreases

(c)

first increases then decreases

(d)

remains same

Answer:

Option (a)

32.

There is a certain optimum pressure ratio for a gas turbine at which its thermal efficiency is maximum. With an increase in turbine temperature, the value of pressure ratio for the peak efficiency would

(a)

remain same

(b)

decreases

(c)

increases

(d)

none of these

Answer:

Option (c)

33.

The work ratio of gas turbine may be improved by

(a)

decreasing  the compression work

(b)

increasing  the compression work

(c)

decreasing the turbine work

(d)

none of these

Answer:

Option (a)

34.

The specific output per kg mass flow rate of a gas turbine (having fixed efficiencies of compressor and turbine and fixed higher and lower temperature) with an increase in pressure ratio will

(a)

increase first at a fast rate and then slow

(b)

increase first at a slow rate and then fast

(c)

decrease continuously

(d)

first increase, reach maximum, and then decrease

Answer:

Option (d)

35.

For an irreversible gas turbine cycle, the efficiency and work ratio both depend on

(a)

pressure ratio alone

(b)

maximum cycle temperature alone

(c)

minimum cycle temperature alone

(d)

both pressure ratio and maximum cycle temperature

Answer:

Option (d)

36.

Which of the following method can be used to improve the thermal efficiency of the open cycle gas turbine plant?

(a)

Intercooling

(b)

Reheating

(c)

Regeneration

(d)

All of the mentioned

Answer:

Option (d)

37.

 In gas turbine, intercooler is placed _____________.

(a)

before low-pressure compressor

(b)

in between low-pressure compressor and high-pressure compressor

(c)

in between high pressure compressor and turbine

(d)

none of the mentioned

Answer:

Option (b)

38.

Intercooling in gas turbines

(a)

decreases net output but increases thermal efficiency

(b)

increases net output but decreases the thermal efficiency

(c)

decreases net output and thermal efficiency both

(d)

increases net output and thermal efficiency both

Answer:

Option (b)

39.

In gas turbines, the work input with intercooling is __________ the work input with no intercooling.

(a)

less than

(b)

more than

(c)

equal to

(d)

any of the mentioned

Answer:

Option (a)

40.

In a gas turbine, what is the function of re-heater?

(a)

Heat inlet air

(b)

Heat exhaust gases

(c)

Heat air coming out of the compressor

(d)

Heat gases coming out of high-pressure turbine

Answer:

Option (d)

Showing 31 to 40 out of 52 Questions