Function calcForcesMoment

src/functionObjects/forces/forces/forces.C:746–876

void Foam::functionObjects::forces::calcForcesMoment()
{
    initialise();

    force_[0] = Zero;
    force_[1] = Zero;
    force_[2] = Zero;

    moment_[0] = Zero;
    moment_[1] = Zero;
    moment_[2] = Zero;

    if (directForceDensity_)
    {
        const volVectorField& fD = obr_.lookupObject<volVectorField>(fDName_);

        const surfaceVectorField::Boundary& Sfb =
            mesh_.Sf().boundaryField();

        forAllConstIter(labelHashSet, patchSet_, iter)
        {
            label patchi = iter.key();

            vectorField Md
            (
                mesh_.C().boundaryField()[patchi] - coordSys_.origin()
            );

            scalarField sA(mag(Sfb[patchi]));

            // Normal force = surfaceUnitNormal*(surfaceNormal & forceDensity)
            vectorField fN
            (
                Sfb[patchi]/sA
               *(
                    Sfb[patchi] & fD.boundaryField()[patchi]
                )
            );

            // Tangential force (total force minus normal fN)
            vectorField fT(sA*fD.boundaryField()[patchi] - fN);

            //- Porous force
            vectorField fP(Md.size(), Zero);

            applyBins(Md, fN, fT, fP, mesh_.C().boundaryField()[patchi]);
        }
    }
    else
    {
        const volScalarField& p = obr_.lookupObject<volScalarField>(pName_);

        const surfaceVectorField::Boundary& Sfb =
            mesh_.Sf().boundaryField();

        tmp<volSymmTensorField> tdevRhoReff = devRhoReff();
        const volSymmTensorField::Boundary& devRhoReffb
            = tdevRhoReff().boundaryField();