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beanlee999 October 21, 2012 12:51

hypersonic flow
 
Hi all,

not sure if anyone can help me on this... I am currently doing flow analysis for hypersonic flows.

Just wondering is there any way of finding the specific heat ratio at temperatures above 3000K? so far, i only found a model based on simple harmonic vibrator and it suits up to 5000 degree rankine.

i am trying to find the Cp for air for above 6000K also. I tried to get the thermodynamic curve fit data for air from nasa website, and it is valid up to 6000K. It seems that this is because of gas dissociation above this temperature. How should i go about obtaining the Cp above 6000K? Do i have to know the dissociation rates prior to this?

Hope some kind people can help to provide me with some guidance to my doubts.

Thanks!

SergeAS October 22, 2012 01:44

Take a look http://en.wikipedia.org/wiki/Atmosph...er_gas_physics especially references concerning real gas models

beanlee999 October 26, 2012 11:54

Is it possible to use perfect gas equations but just modifying the specific heat ratio, to obtain post shock gas stagnation properties?

I seem to have read it somewhere...

SergeAS October 26, 2012 12:30

Quote:

Originally Posted by beanlee999 (Post 388724)
Is it possible to use perfect gas equations but just modifying the specific heat ratio, to obtain post shock gas stagnation properties?

I seem to have read it somewhere...

Yes, it is possible. But if you have full real gas model data in equilibrium assumption, enough to use the tabulated data for the thermodynamic parameters and transport coefficients as a function of temperature, pressure dependence in equilibrium model is much less pronounced and can be neglected


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