[agustinvo]

Hi,


for a certain simulation I need to define a fixed value for a patch in function of all the cells which are on the normal direction to the patch. I need to recognize these cells, and compute a value in function of these cells.


As the mesh is just a prism, I was thinking to filter in function of a cell coordinate (with the same coordinate value the face has), but I was wondering if there is another "easier way" for this, like considering the patch normal vector, etc.


Thanks in advance for your tips and advices!

[JeremyChvlr]

Hi,
I would like to have something like that too, have you found the solution?


Jérémy

[agustinvo]

Hi
Unfortunately I haven't found any other way to compute this.

[JeremyChvlr]

Hi, I think I found the good way to do that, maybe we don't wan't to do the same thing but I share it with you. It is very inspired by another topic on this forum but I can't find it anymore sorry

#include "wallDist.H"
#include "wallFvPatch.H"






 const fvPatchList& patches = mesh.boundary();
volScalarField y = wallDist(mesh).y();
scalar tol = 0.0000001 //Fixe it has you need
const surfaceVectorField& Cf = mesh.Cf();
const volVectorField& C = mesh.C();
dynamicList<scalar> listOfCells

forAll(patches,patchi)
{
  const fvPatch& currPatch = patches[patchi];
  label nFaces = mesh.boundaryMesh()[patchi].size();
  if(isType<wallFvPatch>(currPatch))
  {
    for(int facei = 0; facei<nFaces; facei++)
        {
        scalar distance;
        distance = Foam::sqrt(sqr(C[cellI].x()-Cf.boundaryField()[patchi][facei].x()) +  sqr(C[cellI].y()-Cf.boundaryField()[patchi][facei].y())+ sqr(C[cellI].z()-   Cf.boundaryField()[patchi][facei].z()));
         scalar yTemp = y[cellI];
         scalar diff = mag(distance - yTemp);
                    if( diff <= tol)

                    {
                     listOfCells.append(cellI)

                      //Here you can add cellI on a list, and you have all cells normal to facei in

                    }
         }
   }
}

In my case I search walls but you can adapt it I think to do what you want.

Note that I use foamExtend 4.1 and some function can be different.
Sorry for my bad english


Jérémy