kOmega.C

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

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

namespace Foam
{
namespace RASModels
{

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

template<class BasicMomentumTransportModel>
void kOmega<BasicMomentumTransportModel>::correctNut()
{
    this->nut_ = k_/omega_;
    this->nut_.correctBoundaryConditions();
    fvConstraints::New(this->mesh_).constrain(this->nut_);
}


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


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


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

template<class BasicMomentumTransportModel>
kOmega<BasicMomentumTransportModel>::kOmega
(
    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
    ),

    betaStar_
    (
        dimensioned<scalar>::lookupOrAddToDict
        (
            "betaStar",
            this->coeffDict_,
            0.09
        )
    ),
    beta_
    (
        dimensioned<scalar>::lookupOrAddToDict
        (
            "beta",
            this->coeffDict_,
            0.072
        )
    ),
    gamma_
    (
        dimensioned<scalar>::lookupOrAddToDict
        (
            "gamma",
            this->coeffDict_,
            0.52
        )
    ),
    alphaK_
    (
        dimensioned<scalar>::lookupOrAddToDict
        (
            "alphaK",
            this->coeffDict_,
            0.5
        )
    ),
    alphaOmega_
    (
        dimensioned<scalar>::lookupOrAddToDict
        (
            "alphaOmega",
            this->coeffDict_,
            0.5
        )
    ),

    k_
    (
        IOobject
        (
            IOobject::groupName("k", alphaRhoPhi.group()),
            this->runTime_.timeName(),
            this->mesh_,
            IOobject::MUST_READ,
            IOobject::AUTO_WRITE
        ),
        this->mesh_
    ),
    omega_
    (
        IOobject
        (
            IOobject::groupName("omega", alphaRhoPhi.group()),
            this->runTime_.timeName(),
            this->mesh_,
            IOobject::MUST_READ,
            IOobject::AUTO_WRITE
        ),
        this->mesh_
    )
{
    bound(k_, this->kMin_);
    bound(omega_, this->omegaMin_);

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


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

template<class BasicMomentumTransportModel>
bool kOmega<BasicMomentumTransportModel>::read()
{
    if (eddyViscosity<RASModel<BasicMomentumTransportModel>>::read())
    {
        betaStar_.readIfPresent(this->coeffDict());
        beta_.readIfPresent(this->coeffDict());
        gamma_.readIfPresent(this->coeffDict());
        alphaK_.readIfPresent(this->coeffDict());
        alphaOmega_.readIfPresent(this->coeffDict());

        return true;
    }
    else
    {
        return false;
    }
}


template<class BasicMomentumTransportModel>
void kOmega<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::Internal divU
    (
        fvc::div(fvc::absolute(this->phi(), U))().v()
    );

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

    // Update omega and G at the wall
    omega_.boundaryFieldRef().updateCoeffs();

    // Turbulence specific dissipation rate equation
    tmp<fvScalarMatrix> omegaEqn
    (
        fvm::ddt(alpha, rho, omega_)
      + fvm::div(alphaRhoPhi, omega_)
      - fvm::laplacian(alpha*rho*DomegaEff(), omega_)
     ==
        gamma_*alpha()*rho()*G*omega_()/k_()
      - fvm::SuSp(((2.0/3.0)*gamma_)*alpha()*rho()*divU, omega_)
      - fvm::Sp(beta_*alpha()*rho()*omega_(), omega_)
      + omegaSource()
      + fvModels.source(alpha, rho, omega_)
    );

    omegaEqn.ref().relax();
    fvConstraints.constrain(omegaEqn.ref());
    omegaEqn.ref().boundaryManipulate(omega_.boundaryFieldRef());
    solve(omegaEqn);
    fvConstraints.constrain(omega_);
    bound(omega_, this->omegaMin_);


    // 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(betaStar_*alpha()*rho()*omega_(), 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

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