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maka July 9, 2008 07:14

cell face side length. I ne
cell face side length.

I need to access the length of cell face in x or z direction. The cells are have hexagonal shape. I thought to use sqrt(magSf) but this will be correction only if dx=dz. Do you know any way to do this. Thansk.

Best regards,

maka July 9, 2008 07:39

I thought of the following but
I thought of the following but it is only valid if mesh resolution in z direction (dz) is uniform.

const fvPatchScalarField& vsfp = vsf.boundaryField()[patchI];
// first cell
scalar cf1 = vsfp[xPatchFaceLabel(0,k)].patch().Cf();
scalar A1 = vsfp[xPatchFaceLabel(0,k)].patch().magSf();

// last cell
scalar cfn = vsfp[xPatchFaceLabel(nx()-1,k)].patch().Cf();
scalar An = vsfp[xPatchFaceLabel(nx()-1,k)].patch().magSf();

// Assuming constant resolution in z direction and cell centered node.
scalar dz = (A1+An)/(2*(cf1+cfn));
scalar dx1 = A1/dz;
scalar dxn = A2/dz;

is there a general solution, like using bounding box on the cell? Thanks.

maka July 9, 2008 07:40

scalar dxn = An/dz; That was a
scalar dxn = An/dz; That was a correction.

maka July 9, 2008 11:37

The above is wrong, the correc
The above is wrong, the correct way is to get: faces from the patch and get the edges. I can do that but the problem is that I can not find the function that gives the faceList from polyPatch for example

vsfp.patch().*?* will give faceList of the patch ?

maka July 10, 2008 07:36

The solution is: vsfp.patch()
The solution is:
vsfp.patch().patch().localFaces()[face_label].edges()[edge_label].centre( tch().patch().localPoints())

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