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-   -   nutUSpaldingWallFunction - nutSpalartAllmarasWallFunction - Automatic Wall Treatment (http://www.cfd-online.com/Forums/main/114102-nutuspaldingwallfunction-nutspalartallmaraswallfunction-automatic-wall-treatment.html)

dogan March 5, 2013 08:40

nutUSpaldingWallFunction - nutSpalartAllmarasWallFunction - Automatic Wall Treatment
 
Hello everyone,

i am currently working on a diffusor case and i am trying to find the best wall function to simulate a centrifugal pump in OpenFOAM. I have tried nutkWallFunction, nutUWallFunction and nutUSpaldingWallFunction. i got pretty good results in especially nutUSpaldingWallFunction.

My turbulence model is kOmegaSST, and i am using openFOAM 2.1.x version.

I have compared the results with CFX kOmegaSST, which uses automatic wall function treatment, and i realised that the OpenFOAM results are as good as CFX results even though nutUSpaldingWallFunction is a continuous wall function treatment.

In this point, i have couple of questions:

1) is there a difference between nutSpalartAllmarasWallFunction (which is used in the earlier versions of OpenFOAM) and nutUSpaldingWallFunction?

2) Is it possible automatic wall treatment in openFoam, and if yes, how?

3) i think the formulation of nutUSpaldingWallFunction is coming from the "Spalding's law of the wall" model, or is there a difference between the formulations of the code and the "law of the wall" theory?

thanks in advance to all of you


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