Mechanical Engineering - Compressors, Gas Dynamics and Gas Turbines - Discussion

Discussion Forum : Compressors, Gas Dynamics and Gas Turbines - Section 1 (Q.No. 7)
7.
The stagnation pressure rise in a centrifugal compressor takes place
in the diffuser only
in the impeller only
in the diffuser and impeller
in the inlet guide vanes only
Answer: Option
Explanation:
No answer description is available. Let's discuss.
Discussion:
6 comments Page 1 of 1.

Lokesh said:   6 years ago
Yes, correct I agree @Nitin.

Nitin said:   7 years ago
Answer is correct.

Because pressure rise due to dynamic is in the impeller and due to static in a diffuser. And we know stagnation means static + dynamic. So answer c is correct.
(2)

Ganesh said:   7 years ago
The correct answer is A since diffuser increases the pressure whereas impeller increases the velocity.

Srinivsa Rao B said:   8 years ago
I completely agree with @Avinash's answer. I think there is a misunderstanding that stagnation pressure. Stagnation pressure is nothing but total pressure.

Please refer the below link for information.

https://en.wikipedia.org/wiki/Stagnation_pressure

Avinash Kumar said:   8 years ago
The answer given is incorrect. It is the static pressure which rises in both diffuser and impeller. The stagnation pressure increases as long as work is done in the impeller but decreases a little bit due to friction in diffuser.

So, the correct answer is [B].

Abdul rajik said:   1 decade ago
The former- attached to the compressor section and is used to reduce velocity incoming air and increase the static pressure. It also changes the radial air flow direction to longitudinal flow before directing it into the combustion section.

The latter- the exhaust gas is expanded to atmospheric pressure via the exhaust diffuser to escape the engine without producing excessive residual thrust.

Post your comments here:

Your comments will be displayed after verification.