Discharge coefficient in function of pressure ratio

Roland R · September 21, 2012, 06:36

Hello,

I calculated compressible high speed flow in steady state.
I determined the discharge coefficient from the results in case of some pressure ratio (pi = 0.6 - 0.125). Based on my calculations, the discharge coefficient is constant in this range. (alha = 0,85) The discharge coefficient was investigated at the full geometry.
What do you think about this? Can it be correct? Is there pressure ratio range where the discharge coeff. changes in the function of pressure ratio?

Thanks
Roland

ghorrocks · September 24, 2012, 22:58

Discharge coefficients can be either constant over pressure ratio or variable. It depends on the details of the set up.

September 21, 2012, 06:36	Discharge coefficient in function of pressure ratio	#1
Roland R Senior Member Roland Rakos Join Date: Mar 2009 Posts: 131 Rep Power: 17	Hello, I calculated compressible high speed flow in steady state. I determined the discharge coefficient from the results in case of some pressure ratio (pi = 0.6 - 0.125). Based on my calculations, the discharge coefficient is constant in this range. (alha = 0,85) The discharge coefficient was investigated at the full geometry. What do you think about this? Can it be correct? Is there pressure ratio range where the discharge coeff. changes in the function of pressure ratio? Thanks Roland

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September 24, 2012, 22:58		#2
ghorrocks Super Moderator Glenn Horrocks Join Date: Mar 2009 Location: Sydney, Australia Posts: 17,854 Rep Power: 144	Discharge coefficients can be either constant over pressure ratio or variable. It depends on the details of the set up.