contactAngleForce.C

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License
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#include "contactAngleForce.H"
#include "addToRunTimeSelectionTable.H"
#include "fvcGrad.H"
#include "unitConversion.H"
#include "meshWavePatchDistMethod.H"

// * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * //

namespace Foam
{
namespace regionModels
{
namespace surfaceFilmModels
{

// * * * * * * * * * * * * * * Static Data Members * * * * * * * * * * * * * //

defineTypeNameAndDebug(contactAngleForce, 0);

// * * * * * * * * * * * * Private Member Functions  * * * * * * * * * * * * //

void contactAngleForce::initialise()
{
    const wordReList zeroForcePatches
    (
        coeffDict_.lookupOrDefault<wordReList>("zeroForcePatches", wordReList())
    );

    if (zeroForcePatches.size())
    {
        const polyBoundaryMesh& pbm = filmModel_.regionMesh().boundaryMesh();
        scalar dLim = coeffDict_.lookup<scalar>("zeroForceDistance");

        Info<< "        Assigning zero contact force within " << dLim
            << " of patches:" << endl;

        labelHashSet patchIDs = pbm.patchSet(zeroForcePatches);

        forAllConstIter(labelHashSet, patchIDs, iter)
        {
            label patchi = iter.key();
            Info<< "            " << pbm[patchi].name() << endl;
        }

        // Temporary implementation until run-time selection covers this case
        patchDistMethods::meshWave dist(filmModel_.regionMesh(), patchIDs);
        volScalarField y
        (
            IOobject
            (
                "y",
                filmModel_.regionMesh().time().timeName(),
                filmModel_.regionMesh(),
                IOobject::NO_READ,
                IOobject::NO_WRITE,
                false
            ),
            filmModel_.regionMesh(),
            dimensionedScalar(dimLength, great)
        );
        dist.correct(y);

        mask_ = pos0(y - dimensionedScalar(dimLength, dLim));
    }
}


// * * * * * * * * * * * * * * * * Constructors  * * * * * * * * * * * * * * //

contactAngleForce::contactAngleForce
(
    const word& typeName,
    surfaceFilmRegionModel& film,
    const dictionary& dict
)
:
    force(typeName, film, dict),
    Ccf_(coeffDict_.lookup<scalar>("Ccf")),
    mask_
    (
        IOobject
        (
            IOobject::modelName("contactForceMask", typeName),
            filmModel_.time().timeName(),
            filmModel_.regionMesh(),
            IOobject::NO_READ,
            IOobject::NO_WRITE
        ),
        filmModel_.regionMesh(),
        dimensionedScalar(dimless, 1.0)
    )
{
    initialise();
}


// * * * * * * * * * * * * * * * * Destructor  * * * * * * * * * * * * * * * //

contactAngleForce::~contactAngleForce()
{}


// * * * * * * * * * * * * * * Member Functions  * * * * * * * * * * * * * * //

tmp<fvVectorMatrix> contactAngleForce::correct(volVectorField& U)
{
    tmp<volVectorField> tForce
    (
        volVectorField::New
        (
            IOobject::modelName("contactForce", typeName),
            filmModel_.regionMesh(),
            dimensionedVector(dimForce/dimVolume, Zero)
        )
    );

    vectorField& force = tForce.ref().primitiveFieldRef();

    const labelUList& own = filmModel_.regionMesh().owner();
    const labelUList& nbr = filmModel_.regionMesh().neighbour();
    const scalarField& V = filmModel_.regionMesh().V();

    const volScalarField& coverage = filmModel_.coverage();

    const tmp<volScalarField> tsigma = filmModel_.sigma();
    const volScalarField& sigma = tsigma();

    const tmp<volScalarField> ttheta = theta();
    const volScalarField& theta = ttheta();

    const volVectorField gradCoverage(fvc::grad(coverage));

    forAll(nbr, facei)
    {
        const label cellO = own[facei];
        const label cellN = nbr[facei];

        label celli = -1;
        if ((coverage[cellO] > 0.5) && (coverage[cellN] < 0.5))
        {
            celli = cellO;
        }
        else if ((coverage[cellO] < 0.5) && (coverage[cellN] > 0.5))
        {
            celli = cellN;
        }

        if (celli != -1 && mask_[celli] > 0.5)
        {
            const scalar invDx = filmModel_.regionMesh().deltaCoeffs()[facei];
            const vector n =
                gradCoverage[celli]/(mag(gradCoverage[celli]) + rootVSmall);
            const scalar cosTheta = cos(degToRad(theta[celli]));
            force[celli] += Ccf_*n*sigma[celli]*(1 - cosTheta)/invDx;
        }
    }

    forAll(coverage.boundaryField(), patchi)
    {
        if (!filmModel_.isCoupledPatch(patchi))
        {
            const fvPatchField<scalar>& coveragePf =
                coverage.boundaryField()[patchi];
            const fvPatchField<scalar>& maskPf = mask_.boundaryField()[patchi];
            const fvPatchField<scalar>& sigmaPf = sigma.boundaryField()[patchi];
            const fvPatchField<scalar>& thetaPf = theta.boundaryField()[patchi];
            const scalarField& invDx = coveragePf.patch().deltaCoeffs();
            const labelUList& faceCells = coveragePf.patch().faceCells();

            forAll(coveragePf, facei)
            {
                if (maskPf[facei] > 0.5)
                {
                    const label cellO = faceCells[facei];

                    if ((coverage[cellO] > 0.5) && (coveragePf[facei] < 0.5))
                    {
                        const vector n =
                            gradCoverage[cellO]
                           /(mag(gradCoverage[cellO]) + rootVSmall);

                        const scalar cosTheta = cos(degToRad(thetaPf[facei]));
                        force[cellO] +=
                            Ccf_*n*sigmaPf[facei]*(1 - cosTheta)/invDx[facei];
                    }
                }
            }
        }
    }

    force /= V;

    if (filmModel_.regionMesh().time().writeTime())
    {
        tForce().write();
    }

    tmp<fvVectorMatrix> tfvm
    (
        new fvVectorMatrix(U, dimForce)
    );

    tfvm.ref() += tForce;

    return tfvm;
}


// * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * //

} // End namespace surfaceFilmModels
} // End namespace regionModels
} // End namespace Foam

// ************************************************************************* //