CFD Online Discussion Forums

CFD Online Discussion Forums (
-   FLUENT (
-   -   Can Fluent Import New Turbulence Model By UDF? (

Andy Cong November 29, 2005 22:57

Can Fluent Import New Turbulence Model By UDF?

I have a new turbulence model, and I want to import it to Fluent by UDF.

Can I do it successfully? If so, how can I do it?(Give some advices)



pratikddhoot March 24, 2016 14:42

Hi, If you have successfully imported a model, I would like to know how. I am struggling on the same issue right now.

LuckyTran March 25, 2016 13:56

This problem is too general for specific answers to be given.

In general, you can make Fluent do anything you want with a UDF. But implementation is specific to what you are trying to do. It depends exactly on what your turbulence model is that you are trying to import. Most models can be implemented just by hooking up a udf for the turbulent viscosity. But the complexity arises from how you want to model the turbulent viscosity. In particular, the model for turbulent viscosity is different for high Re and low Re models.

pratikddhoot March 25, 2016 14:09

While I understand that I just have to play with turbulent viscosity in UDF as required in my model, I am trying to modify the Spalart Allmaras model into a zero equation model with a function for turbulent viscosity at each grid cell. Is this doable and what changes will be necessary to convert a 1-eq model to a 0-eq model?


LuckyTran March 25, 2016 14:14

In the Fluent customization manual, there is an example you can follow.2.3.44. DEFINE_TURBULENT_VISCOSITY

All times are GMT -4. The time now is 10:42.