Non equilibrium wall function : pressure acquisition problem

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 October 6, 2010, 18:52 Non equilibrium wall function : pressure acquisition problem #1 New Member   Mattia Maffioletti Join Date: Oct 2009 Posts: 1 Rep Power: 0 Hi everyone. I'm trying to implement a fluent-type wall function sensitized to pressure gradient, i.e. "non-equilibrium WF". There is no problem in epsilon/omega WF when I get the pressure gradient, needed for my calculation, in this way: const volScalarField& P = db().lookupObject("p"); volVectorField grdntP = fvc::grad(P); If I apply the same procedure in nutSpalartAllmarasWF ( that follows the general Spalding law-of-the-wall but it has to be sentivized to pressure gradient, too!) the solution explode in an unexplainable way. I've already tried to debug my code on every line that I added and I've concluded that the problematic line is the second I wrote before. My idea is that this procedure applied to nut-WF result in an unintentional modify of the pressure field, but I thin it's a weak idea, if I had understood OF works. Any idea?

October 10, 2010, 04:45
#2
New Member

Maolong LIU
Join Date: Apr 2010
Location: Japan
Posts: 28
Rep Power: 8
Hi, have you solved this problem?
I am now also trying to write a new wall function including pressure gradient.

Quote:
 Originally Posted by MafioTia Hi everyone. I'm trying to implement a fluent-type wall function sensitized to pressure gradient, i.e. "non-equilibrium WF". There is no problem in epsilon/omega WF when I get the pressure gradient, needed for my calculation, in this way: const volScalarField& P = db().lookupObject("p"); volVectorField grdntP = fvc::grad(P); If I apply the same procedure in nutSpalartAllmarasWF ( that follows the general Spalding law-of-the-wall but it has to be sentivized to pressure gradient, too!) the solution explode in an unexplainable way. I've already tried to debug my code on every line that I added and I've concluded that the problematic line is the second I wrote before. My idea is that this procedure applied to nut-WF result in an unintentional modify of the pressure field, but I thin it's a weak idea, if I had understood OF works. Any idea?