PDRkEpsilon.C

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#include "PDRkEpsilon.H"
#include "PDRDragModel.H"
#include "addToRunTimeSelectionTable.H"
 
// * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * //
 
namespace Foam
{
namespace compressible
{
namespace RASModels
{
 
// * * * * * * * * * * * * * * Static Data Members * * * * * * * * * * * * * //
 
defineTypeNameAndDebug(PDRkEpsilon, 0);
addToRunTimeSelectionTable(RASModel, PDRkEpsilon, dictionary);
 
// * * * * * * * * * * * * Protected Member Functions  * * * * * * * * * * * //
 
tmp<volScalarField> PDRkEpsilon::boundEpsilon()
{
    tmp<volScalarField> tCmuk2(Cmu_*sqr(k_));
    epsilon_ = max(epsilon_, tCmuk2()/(nutMaxCoeff_*nu()));
    return tCmuk2;
}
 
 
void PDRkEpsilon::correctNut()
{
    nut_ = Cmu_*sqr(k_)/epsilon_;
    nut_.correctBoundaryConditions();
    fvConstraints::New(mesh_).constrain(nut_);
}
 
 
// * * * * * * * * * * * * * * * * Constructors  * * * * * * * * * * * * * * //
 
PDRkEpsilon::PDRkEpsilon
(
    const geometricOneField& alpha,
    const volScalarField& rho,
    const volVectorField& U,
    const surfaceScalarField& alphaRhoPhi,
    const surfaceScalarField& phi,
    const viscosity& transport,
    const word& modelName
)
:
    Foam::RASModels::kEpsilon<compressible::momentumTransportModel>
    (
        geometricOneField(),
        rho,
        U,
        phi,
        phi,
        transport,
        modelName
    ),
 
    C4_
    (
        dimensioned<scalar>::lookupOrAddToDict
        (
            "C4",
            coeffDict_,
            0.1
        )
    )
{}
 
 
// * * * * * * * * * * * * * * * * * Destructor  * * * * * * * * * * * * * * //
 
PDRkEpsilon::~PDRkEpsilon()
{}
 
 
// * * * * * * * * * * * * * * * Member Functions  * * * * * * * * * * * * * //
 
bool PDRkEpsilon::read()
{
    if (RASModel::read())
    {
        C4_.readIfPresent(coeffDict_);
        return true;
    }
    else
    {
        return false;
    }
}
 
 
void PDRkEpsilon::correct()
{
    if (!turbulence_)
    {
        // Re-calculate viscosity
        nut_ = Cmu_*sqr(k_)/epsilon_;
        nut_.correctBoundaryConditions();
 
        return;
    }
 
    RASModel::correct();
 
    volScalarField divU(fvc::div(phi_/fvc::interpolate(rho_)));
 
    if (mesh_.moving())
    {
        divU += fvc::div(mesh_.phi());
    }
 
    tmp<volTensorField> tgradU = fvc::grad(U_);
    volScalarField G(GName(), rho_*nut_*(tgradU() && dev(twoSymm(tgradU()))));
    tgradU.clear();
 
    // Update epsilon and G at the wall
    epsilon_.boundaryFieldRef().updateCoeffs();
 
    // Add the blockage generation term so that it is included consistently
    // in both the k and epsilon equations
    const volScalarField& betav =
        U_.db().lookupObject<volScalarField>("betav");
 
    const volScalarField& Lobs =
        U_.db().lookupObject<volScalarField>("Lobs");
 
    const PDRDragModel& drag =
        U_.db().lookupObject<PDRDragModel>("PDRDragModel");
 
    volScalarField GR(drag.Gk());
 
    volScalarField LI
        (C4_*(Lobs + dimensionedScalar(dimLength, rootVSmall)));
 
    // Dissipation equation
    tmp<fvScalarMatrix> epsEqn
    (
        betav*fvm::ddt(rho_, epsilon_)
      + fvm::div(phi_, epsilon_)
      - fvm::laplacian(rho_*DepsilonEff(), epsilon_)
     ==
        C1_*betav*G*epsilon_/k_
      + 1.5*pow(Cmu_, 3.0/4.0)*GR*sqrt(k_)/LI
      - fvm::SuSp(((2.0/3.0)*C1_)*betav*rho_*divU, epsilon_)
      - fvm::Sp(C2_*betav*rho_*epsilon_/k_, epsilon_)
    );
 
    epsEqn.ref().relax();
 
    epsEqn.ref().boundaryManipulate(epsilon_.boundaryFieldRef());
 
    solve(epsEqn);
    boundEpsilon();
 
 
    // Turbulent kinetic energy equation
 
    tmp<fvScalarMatrix> kEqn
    (
        betav*fvm::ddt(rho_, k_)
      + fvm::div(phi_, k_)
      - fvm::laplacian(rho_*DkEff(), k_)
     ==
        betav*G + GR
      - fvm::SuSp((2.0/3.0)*betav*rho_*divU, k_)
      - fvm::Sp(betav*rho_*epsilon_/k_, k_)
    );
 
    kEqn.ref().relax();
    solve(kEqn);
    bound(k_, kMin_);
 
    correctNut();
}
 
 
// * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * //
 
} // End namespace RASModels
} // End namespace compressible
} // End namespace Foam
 
// ************************************************************************* //