kEqn.C

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#include "kEqn.H"
#include "fvModels.H"
#include "fvConstraints.H"
 
// * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * //
 
namespace Foam
{
namespace LESModels
{
 
// * * * * * * * * * * * * Protected Member Functions  * * * * * * * * * * * //
 
template<class BasicMomentumTransportModel>
void kEqn<BasicMomentumTransportModel>::correctNut()
{
    this->nut_ = Ck_*sqrt(k_)*this->delta();
    this->nut_.correctBoundaryConditions();
    fvConstraints::New(this->mesh_).constrain(this->nut_);
}
 
 
template<class BasicMomentumTransportModel>
tmp<fvScalarMatrix> kEqn<BasicMomentumTransportModel>::kSource() const
{
    return tmp<fvScalarMatrix>
    (
        new fvScalarMatrix
        (
            k_,
            dimVolume*this->rho_.dimensions()*k_.dimensions()
            /dimTime
        )
    );
}
 
 
// * * * * * * * * * * * * * * * * Constructors  * * * * * * * * * * * * * * //
 
template<class BasicMomentumTransportModel>
kEqn<BasicMomentumTransportModel>::kEqn
(
    const alphaField& alpha,
    const rhoField& rho,
    const volVectorField& U,
    const surfaceScalarField& alphaRhoPhi,
    const surfaceScalarField& phi,
    const viscosity& viscosity,
    const word& type
)
:
    LESeddyViscosity<BasicMomentumTransportModel>
    (
        type,
        alpha,
        rho,
        U,
        alphaRhoPhi,
        phi,
        viscosity
    ),
 
    k_
    (
        IOobject
        (
            this->groupName("k"),
            this->runTime_.name(),
            this->mesh_,
            IOobject::MUST_READ,
            IOobject::AUTO_WRITE
        ),
        this->mesh_
    ),
 
    Ck_("Ck", this->coeffDict(), 0.094)
{
    bound(k_, this->kMin_);
}
 
 
// * * * * * * * * * * * * * * * Member Functions  * * * * * * * * * * * * * //
 
template<class BasicMomentumTransportModel>
bool kEqn<BasicMomentumTransportModel>::read()
{
    if (LESeddyViscosity<BasicMomentumTransportModel>::read())
    {
        Ck_.readIfPresent(this->coeffDict());
 
        return true;
    }
    else
    {
        return false;
    }
}
 
 
template<class BasicMomentumTransportModel>
tmp<volScalarField> kEqn<BasicMomentumTransportModel>::epsilon() const
{
    return volScalarField::New
    (
        this->groupName("epsilon"),
        this->Ce_*k()*sqrt(k())/this->delta()
    );
}
 
 
template<class BasicMomentumTransportModel>
void kEqn<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_)
    );
 
    LESeddyViscosity<BasicMomentumTransportModel>::correct();
 
    volScalarField divU(fvc::div(fvc::absolute(this->phi(), U)));
 
    tmp<volTensorField> tgradU(fvc::grad(U));
    volScalarField G(this->GName(), nut*(tgradU() && dev(twoSymm(tgradU()))));
    tgradU.clear();
 
    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(this->Ce_*alpha*rho*sqrt(k_)/this->delta(), 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 LESModels
} // End namespace Foam
 
// ************************************************************************* //