Location of faceCentres and cellCentres
 

Dear Foamers,

I have a simple question, but can not find the answer in the user or programmer guide.
How is the cellCentre determined in OF?

I thought the cellCentre-vector is determined by the centre of mass in the cell e.g.:

x_centre = Int(x*dV) / volume of cell
y_centre = Int(y*dV) / volume of cell
z_centre = Int(z*dV) / volume of cell

Only in this way the volume integration in finite volume method would be second order accurate, but i can not find the porof in the documentation.
Do you remember, where to find the proof or is the cell centre determined in a different way?

In addition, I would need to know, if faceCentre are determined in the same way. So are teh face centres the real centroid of the face Area:

x_centre = Int(x*dA) / area of face
y_centre = Int(y*dA) / area of face

Best thanks for any reply,
K.C.