LaunderSharmaKE.C

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#include "LaunderSharmaKE.H"
#include "fvModels.H"
#include "fvConstraints.H"
#include "bound.H"

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

namespace Foam
{
namespace RASModels
{

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

template<class BasicMomentumTransportModel>
tmp<volScalarField> LaunderSharmaKE<BasicMomentumTransportModel>::fMu() const
{
    return exp(-3.4/sqr(scalar(1) + sqr(k_)/(this->nu()*epsilon_)/50.0));
}


template<class BasicMomentumTransportModel>
tmp<volScalarField> LaunderSharmaKE<BasicMomentumTransportModel>::f2() const
{
    return
        scalar(1)
      - 0.3*exp(-min(sqr(sqr(k_)/(this->nu()*epsilon_)), scalar(50.0)));
}


template<class BasicMomentumTransportModel>
void LaunderSharmaKE<BasicMomentumTransportModel>::correctNut()
{
    this->nut_ = Cmu_*fMu()*sqr(k_)/epsilon_;
    this->nut_.correctBoundaryConditions();
    fvConstraints::New(this->mesh_).constrain(this->nut_);
}


template<class BasicMomentumTransportModel>
tmp<fvScalarMatrix>
LaunderSharmaKE<BasicMomentumTransportModel>::kSource() const
{
    return tmp<fvScalarMatrix>
    (
        new fvScalarMatrix
        (
            k_,
            dimVolume*this->rho_.dimensions()*k_.dimensions()
            /dimTime
        )
    );
}


template<class BasicMomentumTransportModel>
tmp<fvScalarMatrix>
LaunderSharmaKE<BasicMomentumTransportModel>::epsilonSource() const
{
    return tmp<fvScalarMatrix>
    (
        new fvScalarMatrix
        (
            epsilon_,
            dimVolume*this->rho_.dimensions()*epsilon_.dimensions()
            /dimTime
        )
    );
}


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

template<class BasicMomentumTransportModel>
LaunderSharmaKE<BasicMomentumTransportModel>::LaunderSharmaKE
(
    const alphaField& alpha,
    const rhoField& rho,
    const volVectorField& U,
    const surfaceScalarField& alphaRhoPhi,
    const surfaceScalarField& phi,
    const viscosity& viscosity,
    const word& type
)
:
    eddyViscosity<RASModel<BasicMomentumTransportModel>>
    (
        type,
        alpha,
        rho,
        U,
        alphaRhoPhi,
        phi,
        viscosity
    ),

    Cmu_
    (
        dimensioned<scalar>::lookupOrAddToDict
        (
            "Cmu",
            this->coeffDict_,
            0.09
        )
    ),
    C1_
    (
        dimensioned<scalar>::lookupOrAddToDict
        (
            "C1",
            this->coeffDict_,
            1.44
        )
    ),
    C2_
    (
        dimensioned<scalar>::lookupOrAddToDict
        (
            "C2",
            this->coeffDict_,
            1.92
        )
    ),
    C3_
    (
        dimensioned<scalar>::lookupOrAddToDict
        (
            "C3",
            this->coeffDict_,
            0
        )
    ),
    sigmak_
    (
        dimensioned<scalar>::lookupOrAddToDict
        (
            "sigmak",
            this->coeffDict_,
            1.0
        )
    ),
    sigmaEps_
    (
        dimensioned<scalar>::lookupOrAddToDict
        (
            "sigmaEps",
            this->coeffDict_,
            1.3
        )
    ),

    k_
    (
        IOobject
        (
            IOobject::groupName("k", alphaRhoPhi.group()),
            this->runTime_.timeName(),
            this->mesh_,
            IOobject::MUST_READ,
            IOobject::AUTO_WRITE
        ),
        this->mesh_
    ),

    epsilon_
    (
        IOobject
        (
            IOobject::groupName("epsilon", alphaRhoPhi.group()),
            this->runTime_.timeName(),
            this->mesh_,
            IOobject::MUST_READ,
            IOobject::AUTO_WRITE
        ),
        this->mesh_
    )
{
    bound(k_, this->kMin_);
    bound(epsilon_, this->epsilonMin_);

    if (type == typeName)
    {
        this->printCoeffs(type);
    }
}


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

template<class BasicMomentumTransportModel>
bool LaunderSharmaKE<BasicMomentumTransportModel>::read()
{
    if (eddyViscosity<RASModel<BasicMomentumTransportModel>>::read())
    {
        Cmu_.readIfPresent(this->coeffDict());
        C1_.readIfPresent(this->coeffDict());
        C2_.readIfPresent(this->coeffDict());
        C3_.readIfPresent(this->coeffDict());
        sigmak_.readIfPresent(this->coeffDict());
        sigmaEps_.readIfPresent(this->coeffDict());

        return true;
    }
    else
    {
        return false;
    }
}


template<class BasicMomentumTransportModel>
void LaunderSharmaKE<BasicMomentumTransportModel>::correct()
{
    if (!this->turbulence_)
    {
        return;
    }

    // Local references
    const alphaField& alpha = this->alpha_;
    const rhoField& rho = this->rho_;
    const surfaceScalarField& alphaRhoPhi = this->alphaRhoPhi_;
    const volVectorField& U = this->U_;
    volScalarField& nut = this->nut_;
    const Foam::fvModels& fvModels(Foam::fvModels::New(this->mesh_));
    const Foam::fvConstraints& fvConstraints
    (
        Foam::fvConstraints::New(this->mesh_)
    );

    eddyViscosity<RASModel<BasicMomentumTransportModel>>::correct();

    volScalarField divU(fvc::div(fvc::absolute(this->phi(), U)));

    // Calculate parameters and coefficients for Launder-Sharma low-Reynolds
    // number model

    volScalarField E(2.0*this->nu()*nut*fvc::magSqrGradGrad(U));
    volScalarField D(2.0*this->nu()*magSqr(fvc::grad(sqrt(k_))));

    tmp<volTensorField> tgradU = fvc::grad(U);
    volScalarField G(this->GName(), nut*(tgradU() && dev(twoSymm(tgradU()))));
    tgradU.clear();


    // Dissipation equation
    tmp<fvScalarMatrix> epsEqn
    (
        fvm::ddt(alpha, rho, epsilon_)
      + fvm::div(alphaRhoPhi, epsilon_)
      - fvm::laplacian(alpha*rho*DepsilonEff(), epsilon_)
     ==
        C1_*alpha*rho*G*epsilon_/k_
      - fvm::SuSp(((2.0/3.0)*C1_ - C3_)*alpha*rho*divU, epsilon_)
      - fvm::Sp(C2_*f2()*alpha*rho*epsilon_/k_, epsilon_)
      + alpha*rho*E
      + epsilonSource()
      + fvModels.source(alpha, rho, epsilon_)
    );

    epsEqn.ref().relax();
    fvConstraints.constrain(epsEqn.ref());
    epsEqn.ref().boundaryManipulate(epsilon_.boundaryFieldRef());
    solve(epsEqn);
    fvConstraints.constrain(epsilon_);
    bound(epsilon_, this->epsilonMin_);


    // Turbulent kinetic energy equation
    tmp<fvScalarMatrix> kEqn
    (
        fvm::ddt(alpha, rho, k_)
      + fvm::div(alphaRhoPhi, k_)
      - fvm::laplacian(alpha*rho*DkEff(), k_)
     ==
        alpha*rho*G - fvm::SuSp(2.0/3.0*alpha*rho*divU, k_)
      - fvm::Sp(alpha*rho*(epsilon_ + D)/k_, k_)
      + kSource()
      + fvModels.source(alpha, rho, k_)
    );

    kEqn.ref().relax();
    fvConstraints.constrain(kEqn.ref());
    solve(kEqn);
    fvConstraints.constrain(k_);
    bound(k_, this->kMin_);

    correctNut();
}


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

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

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