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-   -   I donbt want to use wall funtions How can I do it (http://www.cfd-online.com/Forums/openfoam-solving/60089-i-donbt-want-use-wall-funtions-how-can-i-do.html)

pablo July 26, 2006 17:35

We are implementing a turbulen
 
We are implementing a turbulence potential model into OpenFOAM, in fact we already done it http://www.cfd-online.com/OpenFOAM_D...part/happy.gif .

in short, I don't wanna use wall function. How can I get turn off this option?

msrinath80 July 26, 2006 19:15

I don't know the answer to you
 
I don't know the answer to your question, but out of curiosity, are you resolving the flow all the way down to the wall (similar to Fluent's Enhanced Wall Treatment approach)?

hjasak July 27, 2006 01:48

The wall functions in OpenFOAM
 
The wall functions in OpenFOAM are implemented by manipulating the generation term, the dissipation on the wall and wall viscosity. Have a look at the following file:

OpenFOAM-1.3/src/turbulenceModels/incompressible/kEpsilon/kEpsilon.C

in kEpsilon::correct() there are 3 #include files:

wallFunctionsI.H
wallDissipationI.H

wallViscosityI.H

The first one specifies G and epilon near the wall, the second one blocks out the calculation of epsilon in near-wall cells and the third one fixes the near-wall viscosity.

If you do not wish to use the wall functions, do not use this in your model. An example of a model with no wall functions is OpenFOAM-1.3/src/turbulenceModels/incompressible/LaunderSharmaKE.

As you can see, equations are solved without manipulation.

Enjoy,

Hrv

P.S. Which model are you implementing + how come we haven't already got it?

pablo July 29, 2006 17:48

as soon as possible...
 
as soon as possible...


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