RNGkEpsilon.C

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#include "RNGkEpsilon.H"
#include <OpenFOAM/addToRunTimeSelectionTable.H>

#include <compressibleRASModels/backwardsCompatibilityWallFunctions.H>

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

namespace Foam
{
namespace compressible
{
namespace RASModels
{

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

defineTypeNameAndDebug(RNGkEpsilon, 0);
addToRunTimeSelectionTable(RASModel, RNGkEpsilon, dictionary);

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

RNGkEpsilon::RNGkEpsilon
(
    const volScalarField& rho,
    const volVectorField& U,
    const surfaceScalarField& phi,
    const basicThermo& thermophysicalModel
)
:
    RASModel(typeName, rho, U, phi, thermophysicalModel),

    Cmu_
    (
        dimensioned<scalar>::lookupOrAddToDict
        (
            "Cmu",
            coeffDict_,
            0.0845
        )
    ),
    C1_
    (
        dimensioned<scalar>::lookupOrAddToDict
        (
            "C1",
            coeffDict_,
            1.42
        )
    ),
    C2_
    (
        dimensioned<scalar>::lookupOrAddToDict
        (
            "C2",
            coeffDict_,
            1.68
        )
    ),
    C3_
    (
        dimensioned<scalar>::lookupOrAddToDict
        (
            "C3",
            coeffDict_,
            -0.33
        )
    ),
    sigmak_
    (
        dimensioned<scalar>::lookupOrAddToDict
        (
            "sigmak",
            coeffDict_,
            0.71942
        )
    ),
    sigmaEps_
    (
        dimensioned<scalar>::lookupOrAddToDict
        (
            "sigmaEps",
            coeffDict_,
            0.71942
        )
    ),
    Prt_
    (
        dimensioned<scalar>::lookupOrAddToDict
        (
            "Prt",
            coeffDict_,
            1.0
        )
    ),
    eta0_
    (
        dimensioned<scalar>::lookupOrAddToDict
        (
            "eta0",
            coeffDict_,
            4.38
        )
    ),
    beta_
    (
        dimensioned<scalar>::lookupOrAddToDict
        (
            "beta",
            coeffDict_,
            0.012
        )
    ),

    k_
    (
        IOobject
        (
            "k",
            runTime_.timeName(),
            mesh_,
            IOobject::NO_READ,
            IOobject::AUTO_WRITE
        ),
        autoCreateK("k", mesh_)
    ),
    epsilon_
    (
        IOobject
        (
            "epsilon",
            runTime_.timeName(),
            mesh_,
            IOobject::NO_READ,
            IOobject::AUTO_WRITE
        ),
        autoCreateEpsilon("epsilon", mesh_)
    ),
    mut_
    (
        IOobject
        (
            "mut",
            runTime_.timeName(),
            mesh_,
            IOobject::NO_READ,
            IOobject::AUTO_WRITE
        ),
        autoCreateMut("mut", mesh_)
    ),
    alphat_
    (
        IOobject
        (
            "alphat",
            runTime_.timeName(),
            mesh_,
            IOobject::NO_READ,
            IOobject::AUTO_WRITE
        ),
        autoCreateAlphat("alphat", mesh_)
    )
{
    mut_ = Cmu_*rho_*sqr(k_)/(epsilon_ + epsilonSmall_);
    mut_.correctBoundaryConditions();

    alphat_ = mut_/Prt_;
    alphat_.correctBoundaryConditions();

    printCoeffs();
}


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

tmp<volSymmTensorField> RNGkEpsilon::R() const
{
    return tmp<volSymmTensorField>
    (
        new volSymmTensorField
        (
            IOobject
            (
                "R",
                runTime_.timeName(),
                mesh_,
                IOobject::NO_READ,
                IOobject::NO_WRITE
            ),
            ((2.0/3.0)*I)*k_ - (mut_/rho_)*dev(twoSymm(fvc::grad(U_))),
            k_.boundaryField().types()
        )
    );
}


tmp<volSymmTensorField> RNGkEpsilon::devRhoReff() const
{
    return tmp<volSymmTensorField>
    (
        new volSymmTensorField
        (
            IOobject
            (
                "devRhoReff",
                runTime_.timeName(),
                mesh_,
                IOobject::NO_READ,
                IOobject::NO_WRITE
            ),
           -muEff()*dev(twoSymm(fvc::grad(U_)))
        )
    );
}


tmp<fvVectorMatrix> RNGkEpsilon::divDevRhoReff(volVectorField& U) const
{
    return
    (
      - fvm::laplacian(muEff(), U) - fvc::div(muEff()*dev2(fvc::grad(U)().T()))
    );
}


bool RNGkEpsilon::read()
{
    if (RASModel::read())
    {
        Cmu_.readIfPresent(coeffDict());
        C1_.readIfPresent(coeffDict());
        C2_.readIfPresent(coeffDict());
        C3_.readIfPresent(coeffDict());
        Prt_.readIfPresent(coeffDict());
        sigmaEps_.readIfPresent(coeffDict());
        Prt_.readIfPresent(coeffDict());
        eta0_.readIfPresent(coeffDict());
        beta_.readIfPresent(coeffDict());

        return true;
    }
    else
    {
        return false;
    }
}


void RNGkEpsilon::correct()
{
    if (!turbulence_)
    {
        // Re-calculate viscosity
        mut_ = rho_*Cmu_*sqr(k_)/(epsilon_ + epsilonSmall_);
        mut_.correctBoundaryConditions();

        // Re-calculate thermal diffusivity
        alphat_ = mut_/Prt_;
        alphat_.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 S2 = (tgradU() && dev(twoSymm(tgradU())));
    tgradU.clear();

    volScalarField G("RASModel::G", mut_*S2);

    volScalarField eta = sqrt(mag(S2))*k_/epsilon_;
    volScalarField eta3 = eta*sqr(eta);

    volScalarField R =
        ((eta*(-eta/eta0_ + scalar(1)))/(beta_*eta3 + scalar(1)));

    // Update espsilon and G at the wall
    epsilon_.boundaryField().updateCoeffs();

    // Dissipation equation
    tmp<fvScalarMatrix> epsEqn
    (
        fvm::ddt(rho_, epsilon_)
      + fvm::div(phi_, epsilon_)
      - fvm::laplacian(DepsilonEff(), epsilon_)
      ==
        (C1_ - R)*G*epsilon_/k_
      - fvm::SuSp(((2.0/3.0)*C1_ + C3_)*rho_*divU, epsilon_)
      - fvm::Sp(C2_*rho_*epsilon_/k_, epsilon_)
    );

    epsEqn().relax();

    epsEqn().boundaryManipulate(epsilon_.boundaryField());

    solve(epsEqn);
    bound(epsilon_, epsilon0_);


    // Turbulent kinetic energy equation

    tmp<fvScalarMatrix> kEqn
    (
        fvm::ddt(rho_, k_)
      + fvm::div(phi_, k_)
      - fvm::laplacian(DkEff(), k_)
      ==
        G - fvm::SuSp(2.0/3.0*rho_*divU, k_)
      - fvm::Sp(rho_*(epsilon_)/k_, k_)
    );

    kEqn().relax();
    solve(kEqn);
    bound(k_, k0_);


    // Re-calculate viscosity
    mut_ = rho_*Cmu_*sqr(k_)/epsilon_;
    mut_.correctBoundaryConditions();

    // Re-calculate thermal diffusivity
    alphat_ = mut_/Prt_;
    alphat_.correctBoundaryConditions();
}


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

} // End namespace RASModels
} // End namespace compressible
} // End namespace Foam

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