Gendou.com Forum: Physics: Friend needs help with a question

Friend needs help with a question

Link | by

Voxyn on 2006-05-21 06:22:02 (edited 2006-05-21 06:43:31)

The original question is as follows:

"Hi guys, got my Advanced Aersospace Propulsion exam tomorrow, just wondering if someone who knew a bit more about it could help me on the revision.

I'm trying to find out the thermal, propulsion and overall efficiency. The information given is as follows:

Mach 3
Ambient Pressure = 8.5kPa
Ambient Temp = 220K
Turbine Inlet Temp = 2450K
(All components frictionless therefore Ideal)
Specific Heat Ratio = 1.4

Any ideas? I'm a little stumped

I think the thermal efficiency would be given by 1 - (T1/T2) so that's not too bad, but the propulsion efficiency I think is given by 2 / [1+(Ue/Uo)], is that right? and if so how do you determine Uo and Ue (Mach number and exhaust outlet velocity???)

And then overall efficiency I haven't a clue.

Hopefully there's a rocket scientist in the house...

Thanks for any help you provide.
If possible please answer before 9am tomorrow, London time.

Back | Reverse |