[Ells96]

Hi everyone,

I'm quite new to programming with OpenFOAM and need some help.

I am trying to create a new scalar field that calculates the total difference in viscosity between a given cell and all of its neighbouring cells. What is the syntax I need to get the value of a variable in a given cell and the value in all cells directly adjacent?

I'm hoping to get this to work for an AMR method and to work in parallel.

Thanks,

Elliott

[mAlletto]

How to get the neighbour of one cell?

Just a few seconds googling helps a lot

[Ells96]

Originally Posted by mAlletto

How to get the neighbour of one cell?

Just a few seconds googling helps a lot

Thank you for this.

I've performed the calculation as shown below, but receive the error that " 'celli' was not declared in this scope". I'm not sure how to properly declare 'celli' as any cell in the mesh. Any help would be appreciated.

Declaration of the variable in the .C file, initialised based on a viscosity field:

    etaGrad_
    (
        IOobject
        (
            "etaGrad" + name,
            U.time().timeName(),
            U.mesh(),
            IOobject::NO_READ,
            IOobject::AUTO_WRITE
        ),
        eta_
    ),

The actual calculation in .C:

   
   const objectRegistry& db();
   const volVectorField& U = db().lookupObject<volVectorField>("U");
   const fvMesh& mesh = U.mesh();
   const labelList& neighbour = mesh.cellCells[celli]();
   
   forAll(neighbour,celli)
   {
      etaGrad_[celli] += mag(eta_[celli] - eta_[neighbour[celli]]);
   }

Declaration in the .H file:

        //- Viscosity gradient field
        volScalarField etaGrad_;