[wernero]

Dear all!

I'm working on a new solver for electromagnetics. I define a material character ('chi'), and read it successfully . Also, volVectorfield 'M' and 'H' are defined.

Let's assume a cellzone named "ironCore" is exist in polymesh. The next calculation is required:

1. for all the cells:
1.1 if the current cell is from "ironCore" cellzone: M[ID]=chi*H[ID].
1.2 otherwise: M[ID]=(0 0 0);

I assume it is possible to create a volScalarField chi, which is zero outside "ironCore". Then the calculation is performed with:

forAll(chi, celli)
{
  M[celli]=chi[celli]*H[celli];
}

but when ironCore is only a small part of the mesh, this is a waste. Is there a way to create a list of all the cells in "ironCore", so I could do the calculation only on those cells? The volVectorField M could be initialized with to (0 0 0), so it should be manipulated only in the specific cellzone

for (ii=first_cell_of_ironCore ; ii<number_of_cells_in_ironCore ; ii++)
{
  M[celli]=chi[celli]*H[celli];
}

thanks in advance...
Or.

[Zeppo]

This code might be a point you can start from:

const fvMesh& mesh = ...;

word cellSetName = "yourCellZoneName";

label zoneID = mesh.cellZones().findZoneID(cellSetName);

if (zoneID == -1)
{
    FatalErrorIn("yourFunctionName")
        << "Cannot find cellZone " << cellSetName << endl
        << "Valid cellZones are " << mesh.cellZones().names()
        << exit(FatalError);
}

const labelList& cells = mesh.cellZones()[zoneID];

Info << "Cells in cellzone " << cellSetName << ":" << endl;
forAll(cells, i)
{
    const label cell = cells[i];
    Info << cell << endl;
}

[wernero]

Thank you very much Sergei.

about the part of

const label cell = cells[i];

is "label cell" the index of the cell in the whole mesh, or the index of the cell in the list "cells"?

If it is the index in the whole mesh, than it is quite what I need, and I could manage from here.


thanks again for helping me,

Or.

[Zeppo]

const label cell = cells[i];

Here cell is a cell index in a whole mesh and you can use it like this

const volScalarField& T = ...
T[cell] = 300.0;