CFD Online Discussion Forums - Manually modifying boundary condition

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Manually modifying boundary condition

Hi,

I would like to change the value of a Dirichlet boundary condition at just one point. I already know the label of the face at which I would like the change (in the global numbering of faces).

I would like an overall idea of the logic of what to do: which classes, members function to use.

Thanks

Hi,

Based on the information provided on post http://www.cfd-online.com/Forums/ope...tml#post190696 , I used the following piece of code to fix the temperature at a specific point at the boundary:

Code:

vector locFace(0.2,0,0.02);



label patchID = mesh.boundaryMesh().findPatchID("down"); 

const polyPatch& cPatch = mesh.boundaryMesh()[patchID];

const vectorField& FaceCentres = cPatch.faceCentres(); 



label T2Face=0;

scalar currDist=mag(FaceCentres[0] - locFace);    



forAll(FaceCentres,i) // in each proc, local loop over boundary faces of "inlet"

{

    if (mag(FaceCentres[i] - locFace) < currDist)

    {

        currDist = mag(FaceCentres[i] - locFace);

        T2Face = i;

    }

}



T.boundaryField()[patchID][T2Face]=350;

Now, I would like to use a fixedGradient condition, which value won't be set using T.boundaryField()[patchID][T2Face]. How can I fix the value of the gradient at a particular point ?

Thanks