CFD Online Discussion Forums

CFD Online Discussion Forums (
-   FLUENT (
-   -   Are there more FLUENT Turbulence Models? (

Travis December 26, 2008 00:00

Are there more FLUENT Turbulence Models?
I'm wondering if anyone has implemented additional user-defined turbulence models in FLUENT? I'm specifically interested in finding (or possibly writing) a curvature-corrected Spalart-Allmaras model. I'd really appreciate everyone's two cents on user-defined turbulence models, and if anyone's willing to share one they've written, it would help me get started! Thanks

PS: I posted this once before, but didn't get any responses despite 40+ hits. I was hoping I might get better luck the second time around.

bubua December 26, 2008 15:25

Re: Are there more FLUENT Turbulence Models?
try to find example in user guide udf

Travis December 26, 2008 21:45

Re: Are there more FLUENT Turbulence Models?
I did... thanks for the thought but that was the first place I looked.

zongtwi December 30, 2008 02:45

Re: Are there more FLUENT Turbulence Models?
Hi, I'm no expert at turbulence modelling, even worse at using UDF to modify them. But you may want to consider changing/modifying the values of the constants of the SA model before going into using UDF. If you look up the documentation, you can see where the constants are being used. You may be able to modify any of these constants to give you the effects of your modified model, without having to write a UDF (which can get nasty!!)

If you really need to use a UDF, you can create your own Turbulent Viscosity equation using the Define_Turbulent_Viscosity macro. If you just want to modify the production and dissipation values, you can use the Define_Source macro.

Hope that helps.

All times are GMT -4. The time now is 02:28.