qZeta.C

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#include "qZeta.H"
#include "fvcMagSqrGradGrad.H"
#include "bound.H"
#include "makeMomentumTransportModel.H"
 
makeMomentumTransportModelTypes
(
    geometricOneField,
    geometricOneField,
    incompressibleMomentumTransportModel
)
 
// * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * //
 
namespace Foam
{
namespace incompressible
{
namespace RASModels
{
 
// * * * * * * * * * * * * * * Static Data Members * * * * * * * * * * * * * //
 
defineTypeNameAndDebug(qZeta, 0);
addToRunTimeSelectionTable
(
    RASincompressibleMomentumTransportModel,
    qZeta,
    dictionary
);
 
// * * * * * * * * * * * Protected Member Functions  * * * * * * * * * * * * //
 
void qZeta::boundZeta()
{
    tmp<volScalarField> tCmuk2(Cmu_*sqr(k_));
    zeta_ = max(zeta_, Cmu_*pow3(q_)/((2*nutMaxCoeff_)*nu()));
}
 
 
tmp<volScalarField> qZeta::fMu() const
{
    const volScalarField Rt(q_*k_/(2.0*nu()*zeta_));
 
    if (anisotropic_)
    {
        return exp((-scalar(2.5) + Rt/20.0)/pow3(scalar(1) + Rt/130.0));
    }
    else
    {
        return
            exp(-6.0/sqr(scalar(1) + Rt/50.0))
           *(scalar(1) + 3.0*exp(-Rt/10.0));
    }
}
 
 
tmp<volScalarField> qZeta::f2() const
{
    tmp<volScalarField> Rt = q_*k_/(2.0*nu()*zeta_);
    return scalar(1) - 0.3*exp(-sqr(Rt));
}
 
 
void qZeta::correctNut()
{
    nut_ = Cmu_*fMu()*sqr(k_)/epsilon_;
    nut_.correctBoundaryConditions();
}
 
 
// * * * * * * * * * * * * * * * * Constructors  * * * * * * * * * * * * * * //
 
qZeta::qZeta
(
    const geometricOneField& alpha,
    const geometricOneField& rho,
    const volVectorField& U,
    const surfaceScalarField& alphaRhoPhi,
    const surfaceScalarField& phi,
    const viscosity& viscosity,
    const word& type
)
:
    eddyViscosity<incompressible::RASModel>
    (
        type,
        alpha,
        rho,
        U,
        alphaRhoPhi,
        phi,
        viscosity
    ),
 
    Cmu_("Cmu", typeDict(type), 0.09),
    C1_("C1", typeDict(type), 1.44),
    C2_("C2", typeDict(type), 1.92),
    sigmaZeta_("sigmaZeta", typeDict(type), 1.3),
    anisotropic_(typeDict(type).lookupOrDefault<Switch>("anisotropic", false)),
    qMin_("qMin", sqrt(kMin_)),
 
    k_
    (
        IOobject
        (
            this->groupName("k"),
            runTime_.name(),
            mesh_,
            IOobject::MUST_READ,
            IOobject::AUTO_WRITE
        ),
        mesh_,
        dimensions::turbulentKineticEnergy
    ),
 
    epsilon_
    (
        IOobject
        (
            this->groupName("epsilon"),
            runTime_.name(),
            mesh_,
            IOobject::MUST_READ,
            IOobject::AUTO_WRITE
        ),
        mesh_,
        dimensions::turbulentEpsilon
    ),
 
    q_
    (
        IOobject
        (
            this->groupName("q"),
            runTime_.name(),
            mesh_,
            IOobject::READ_IF_PRESENT,
            IOobject::AUTO_WRITE
        ),
        sqrt(max(k_, kMin_)),
        k_.boundaryField().types()
    ),
 
    zeta_
    (
        IOobject
        (
            this->groupName("zeta"),
            runTime_.name(),
            mesh_,
            IOobject::READ_IF_PRESENT,
            IOobject::AUTO_WRITE
        ),
        epsilon_/(2.0*q_),
        epsilon_.boundaryField().types()
    )
{
    boundZeta();
}
 
 
// * * * * * * * * * * * * * * * Member Functions  * * * * * * * * * * * * * //
 
bool qZeta::read()
{
    if (eddyViscosity<incompressible::RASModel>::read())
    {
        Cmu_.readIfPresent(typeDict());
        C1_.readIfPresent(typeDict());
        C2_.readIfPresent(typeDict());
        sigmaZeta_.readIfPresent(typeDict());
        anisotropic_.readIfPresent("anisotropic", typeDict());
 
        qMin_.readIfPresent(*this);
 
        return true;
    }
    else
    {
        return false;
    }
}
 
 
void qZeta::correct()
{
    if (!turbulence_)
    {
        return;
    }
 
    eddyViscosity<incompressible::RASModel>::correct();
 
    volScalarField G(GName(), nut_/(2.0*q_)*2*magSqr(symm(fvc::grad(U_))));
    const volScalarField E(nu()*nut_/q_*fvc::magSqrGradGrad(U_));
 
    // Zeta equation
    tmp<fvScalarMatrix> zetaEqn
    (
        fvm::ddt(zeta_)
      + fvm::div(phi_, zeta_)
      - fvm::laplacian(DzetaEff(), zeta_)
     ==
        (2.0*C1_ - 1)*G*zeta_/q_
      - fvm::SuSp((2.0*C2_*f2() - dimensionedScalar(1.0))*zeta_/q_, zeta_)
      + E
    );
 
    zetaEqn.ref().relax();
    solve(zetaEqn);
    boundZeta();
 
 
    // q equation
    tmp<fvScalarMatrix> qEqn
    (
        fvm::ddt(q_)
      + fvm::div(phi_, q_)
      - fvm::laplacian(DqEff(), q_)
     ==
        G - fvm::Sp(zeta_/q_, q_)
    );
 
    qEqn.ref().relax();
    solve(qEqn);
    bound(q_, qMin_);
    boundZeta();
 
    // Re-calculate k and epsilon
    k_ = sqr(q_);
    k_.correctBoundaryConditions();
 
    epsilon_ = 2*q_*zeta_;
    epsilon_.correctBoundaryConditions();
 
    correctNut();
}
 
 
// * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * //
 
} // End namespace RASModels
} // End namespace incompressible
} // End namespace Foam
 
// ************************************************************************* //