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Adam September 29, 2006 07:17

Pressure Gradient Parameter
Has anyone had experience with calculating the pressure gradient paremeter and using this during the solver run?

The transition model uses this for its calculations, but i can't find any reference to that variable in the manuals, and it requres the calculation of the momentum thickness at every streamwise point in the flow, which will prove to be hard to do i think.



TB October 1, 2006 20:30

Re: Pressure Gradient Parameter
hmmm.... I'll try to help. If you're looking for pressure gradient parameter for the boundary layer flow, the formula should be: (theta/U)*(dU/ds) where dU/ds is local free stream velocity gradient and theta is the momentum thickness.

However, I didn't calculate this during solver run, only at the end of simulation. Are you working on Transient or steady state simulation?

Adam October 2, 2006 04:03

Re: Pressure Gradient Parameter
I'm running both steady state and transient.

Its the automatic calculation of the momentum thickness that is causing me some problems. I know that CFX must do it for their transition model, but am not sure if I can get access to that part of the code.


TB October 2, 2006 06:23

Re: Pressure Gradient Parameter
As I'm aware, calculation of momentum thickness always involves some integration of velocity profile. The quickest way is to contact your support for solutions.

Kiddo October 3, 2006 08:50

Re: Pressure Gradient Parameter
Hello, try to use UserFortran, there's a default subroutine: for ex.


TB October 4, 2006 04:27

Re: Pressure Gradient Parameter
Hi... I think that's not the idea of a pressure gradient parameter.

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