Steam and Gas Turbines Multiple Choice Questions on ” Design of Turbine Flow Passages”.
1. A turbine having alternate blades and nozzles is called as _______________
a) Impulse turbine
b) Reaction turbine
c) Impulse & Reaction turbine
d) None of the mentioned
Answer: a
Clarification: When blades and nozzles are arranged in alternate manner pressure loss can be reduced and hence it is called an impulse turbine.
2. Multi stage arrangement of turbines is called as __________
a) Impulse turbine
b) Reaction turbine
c) Compounding
d) None of the mentioned
Answer: c
Clarification: Multi stage arrangement of turbines reduces the pressure loss and velocity losses and hence it is called as compounding.
3. Compounding __________ efficiency at low speed.
a) decrease
b) increase
c) maximizes
d) none of the mentioned
Answer: b
Clarification: Even at low speeds velocity wastage is prevented and hence efficiency is increased.
4. In pressure compounded turbines moving nozzles are followed by turbine blades.
a) True
b) False
Answer: b
Clarification: In pressure compounding fixed nozzles are followed by moving blades.
5. In pressure compounded turbines flow passage is from ______________
a) moving nozzles to fixed blades
b) fixed nozzles to moving blades
c) fixed blades to moving nozzles
d) none of the mentioned
Answer: b
Clarification: In pressure compounded turbines pressure drop is reduced into stages reducing the pressure loss and hence increasing the efficiency. Hence in pressure compounded turbines flow passage if from fixed nozzles to moving blades.
6. In velocity compounded turbines flow passage is from ____________
a) moving blades to fixed nozzles
b) fixed nozzles to moving blades
c) fixed blades to moving nozzles
d) none of the mentioned
Answer: d
Clarification: In velocity compounded turbines velocity drop is maintained in stages and hence reducing velocity loses. Hence in velocity compounded turbines flow passage is from fixed nozzles to multiple rows of moving blades alternating with fixed blades.
7. A velocity compounded impulse turbine is also called as __________
a) Curtis wheel
b) Pressure compounded
c) Curtis wheel & Pressure compounded
d) None of the mentioned
Answer: a
Clarification: Velocity compounded turbines are invented by a scientist called Curtis and hence it is named after his name.
8. Reaction turbine is also called as _________
a) Impulse turbine
b) Curtis wheel
c) Parsons turbine
d) None of the mentioned
Answer: c
Clarification: Reaction turbine was invented by a scientist names Parson and hence it was named after his name.
9. A turbine comprising of fixed blades and moving nozzles is called as reaction turbines.
a) True
b) False
Answer: a
Clarification: In reaction turbines the reaction produced when steam hits the turbine is also utilized to produce power output.
10. Compounding is used for _________ power applications.
a) low
b) high
c) medium
d) none of the mentioned
Answer: b
Clarification: In compounding high powers are produced at low speeds also. Hence for low power production compounding need not be used.