Steam Nozzles and Turbines MCQ with Answers

106) The pressure velocity compounded impulse turbine allows a bigger pressure drop and hence __________ number of stages are required.

Answer is:

less

107) If the critical pressure ratio for steam is 0.546, then the steam is initially

Answer is:

superheated steam

108) Which of the following statement is wrong?

The critical pressure gives the velocity of steam at the throat equal to the velocity of sound.

The flow in the convergent portion of the nozzle is sub-sonic.

The flow in the divergent portion of the nozzle is super-sonic.

To increase the velocity of steam above sonic velocity (super-sonic) by expanding steam below the critical pressure, the divergent portion for the nozzle is not necessary.

Answer is:

To increase the velocity of steam above sonic velocity (super-sonic) by expanding steam below the critical pressure, the divergent portion for the nozzle is not necessary.

109) The maximum efficiency of a De-Laval turbine is (where ? = Nozzle angle)

Answer is:

cos² ?

110) The pressure compounded impulse turbine as compared to velocity compounded turbine require __________ number of stages.

Answer is:

106) The pressure velocity compounded impulse turbine allows a bigger pressure drop and hence __________ number of stages are required.

less

107) If the critical pressure ratio for steam is 0.546, then the steam is initially

superheated steam

108) Which of the following statement is wrong?

To increase the velocity of steam above sonic velocity (super-sonic) by expanding steam below the critical pressure, the divergent portion for the nozzle is not necessary.

109) The maximum efficiency of a De-Laval turbine is (where ? = Nozzle angle)

cos2 ?

110) The pressure compounded impulse turbine as compared to velocity compounded turbine require __________ number of stages.

more

cos² ?