Multiphase Compressible Turbulence Model

gpwakeham · September 26, 2011, 05:02

Hi I'am trying to simulate compressible cavitating flow, there are various papers I have read stating you need to have the beta and beta* coefficients as variables of the mach number. Now I have tried using CEL functions to do this but get an error saying that the coeffs must be calculated to a constant value (and thus cannot vary). Is there any way to get around this?

Thank you for your time.

ghorrocks · September 26, 2011, 07:21

Variable constants is not implemented in CFX so it cannot do it.

But there is always a way. Have a look in the VARIABLES file, I think it is in the /etc/ directory. Find the beta and beta* variables and remove the bit forcing them to be constant values. There is a chance this will allow it, but be aware the limitation was put in there for good reason so there is a high probability this will not work.

gpwakeham · September 26, 2011, 07:50

Thank you very much, I'll check it out

September 26, 2011, 05:02	Multiphase Compressible Turbulence Model	#1
gpwakeham New Member George Wakeham Join Date: Sep 2011 Posts: 5 Rep Power: 15	Hi I'am trying to simulate compressible cavitating flow, there are various papers I have read stating you need to have the beta and beta* coefficients as variables of the mach number. Now I have tried using CEL functions to do this but get an error saying that the coeffs must be calculated to a constant value (and thus cannot vary). Is there any way to get around this? Thank you for your time.

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September 26, 2011, 07:21		#2
ghorrocks Super Moderator Glenn Horrocks Join Date: Mar 2009 Location: Sydney, Australia Posts: 17,852 Rep Power: 144	Variable constants is not implemented in CFX so it cannot do it. But there is always a way. Have a look in the VARIABLES file, I think it is in the /etc/ directory. Find the beta and beta* variables and remove the bit forcing them to be constant values. There is a chance this will allow it, but be aware the limitation was put in there for good reason so there is a high probability this will not work.

September 26, 2011, 07:50		#3
gpwakeham New Member George Wakeham Join Date: Sep 2011 Posts: 5 Rep Power: 15	Thank you very much, I'll check it out