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Old 7th Sep 2005, 18:06
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Graviman
 
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Off topic diversion...

KMS,

Just read:

"As an aside, I was looking through an engine book on turbines and found info on the convergent/divergent duct. It appears that there is a misprint explaining temp increases/decreases in relation to velocity and pressure."

Con-Di nozzles are a funny beast. The idea is to get the flow to mach 1 at the end of the convergent section. The flow in the divergent section is all supersonic, so subsonic pressure and temp laws no longer apply. Look up 1D Rayleigh flow if you want to understand further how a Con-Di can accelerate flow to multiple supersonic nos. Basically a continous shock wave means the expanding flow is also accelerating, while the pressure drops (don't recall what happens to temp).

Mart

Last edited by Graviman; 7th Sep 2005 at 18:26.
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