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-   -   patch calculated inlet (http://www.cfd-online.com/Forums/openfoam/82065-patch-calculated-inlet.html)

idrama November 15, 2010 15:36

patch calculated inlet
 
Hello Foamers,

can anybody explain the meaning of the patch calculated. Especially, in the interFoam tutorials (damBreak etc.) where the atmosphere patch is endowed with

atmosphere
{
type calculated;
value uniform 0;
}

Cheers in advance

herbert November 16, 2010 04:35

Hello Claus,

the calculated patch is the default type of a patch. It is not a boundary condition but it only holds the field values on the patch faces. This is why you aren't allowed to solve an equation for a field that has patch type calculated anywhere.

Normally, you find this patch inside fields that are derived from other variables. In your case I think it is from field p whereas the solver is only solving for pd! p is only provided for postprocessing etc.

Hope it helps,
Stefan

idrama November 16, 2010 05:54

Ah, Okay! I think I have understood. Let me say it again in this way, the nut field, for instance, is not really solved by an equation, so it does not need BC's. However, I have to assign one, but the values on the respective patch are obtain from k-e-eq. In other word, I let OpenFOAM know that that nut at the values for the respective patch is obtain from a different source.

I understood, but I cannot yet explained! But I will.

Cheers

idrama November 16, 2010 05:56

Another question: unfortunately, I ran a simulation where I assigned for a nut patch zeroGradient. Does it matters?


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