Mechanical Engineering - Steam Nozzles and Turbines
Exercise :: Steam Nozzles and Turbines - Section 2
21.
The ratio of the isentropic heat drop to the heat supplied, is called
A.
reheat factor B.
stage efficiency C.
internal efficiency D.
Rankine efficiency
Answer: Option D
Explanation:
22.
When the cross-section of a nozzle first increases from its entrance to throat, and then decreases from its throat to exit, it is not a convergent-divergent nozzle.
Answer: Option A
Explanation:
23.
The efficiency ratio is the ratio of total useful heat drop to the total isentropic heat drop.
Answer: Option A
Explanation:
24.
The purpose of governing in steam turbines is to
A.
maintain the speed of the turbine B.
reduce the effective heat drop C.
reheat the steam and improve its quality D.
completely balance against end thrust
Answer: Option A
Explanation:
25.
De-Laval turbines are mostly used
A.
where low speeds are required B.
for small power purposes and low speeds C.
for large power purposes D.
for small power purposes and high speeds
Answer: Option D
Explanation: