Steam and Gas Turbines Multiple Choice Questions on “Design of Nozzles”.
1. Nozzle is used to control direction or characteristics of flow.
a) True
b) False
Answer: a
Clarification: Nozzle is used to control the direction and characteristics of flow.
2. Nozzles are used to control the ___________
a) temperature
b) rate of flow
c) mass flow rate
d) none of the mentioned
Answer: b
Clarification: Nozzles are used to control the rate, speed, direction of flow.
3. A nozzle used to send fluid in coherent stream is called as ________
a) jet
b) high velocity nozzle
c) every nozzle sends fluid in coherent stream
d) none of the mentioned
Answer: a
Clarification: A nozzle used to send the fluid in coherent stream is called as jet.
4. In fountains the type of nozzle used is _______
a) none of the mentioned
b) turbulent jet
c) high speed nozzle
d) laminar jet
Answer: d
Clarification: Laminar jet nozzle is used to convert the fluid in laminar flow.
5. Nozzles used in blast furnaces are called as _______
a) jet
b) hot blast
c) tuyeres
d) none of the mentioned
Answer: c
Clarification: Nozzles used in blast furnaces are called tuyeres.
6. If mach number is less than one then its flow is ______________
a) subsonic flow
b) turbulent flow
c) laminar flow
d) none of the mentioned
Answer: a
Clarification: If M<1 then it is subsonic flow.
7. Nozzle used in rocket engine is __________
a) convergent nozzle
b) divergent nozzle
c) convergent – Divergent nozzle
d) none of the mentioned
Answer: c
Clarification: In rocket air flows from convergent section first and then from divergent section.
8. In rocket engine the flow in the throat of the nozzle is __________
a) subsonic
b) laminar
c) turbulent
d) none of the mentioned
Answer: a
Clarification: In the throat of nozzle mach number is less than one which indicates the flow is subsonic.
9. When mach number is greater than one the flow is ________
a) subsonic
b) supersonic
c) laminar
d) none of the mentioned
Answer: b
Clarification: When M>1 the flow is supersonic.
10. In rocket engines the amount of expansion in Nozzle determines the __________
a) exit temperature
b) exit pressure
c) exit temperature & pressure
d) none of the mentioned
Answer: c
Clarification: When the flow is subsonic, air in nozzle expands isoentropically and hence exit temperature and exit pressure depends on the amount of expansion.