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    Website: https://hzdr.de

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#include "KetterlExtendedGradient.H"

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

namespace Foam
{
namespace LESModels
{

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

template<class BasicMomentumTransportModel>
tmp<volSymmTensorField> KetterlExtendedGradient<BasicMomentumTransportModel>::B
(
    const rhoField& rho,
    const volVectorField& U
) const
{
    volVectorField gradAlpha(gradWrapper(this->alpha_));
    gradAlpha *= pos(mag(gradAlpha) - thresholdGradAlpha_);

    volVectorField gradRho(gradWrapper(rho));
    gradRho *= pos(mag(gradRho) - thresholdGradRho_);

    volTensorField gradU(fvc::grad(U));
    gradU *= pos(mag(gradU) - thresholdGradU_);
    const volTensorField gradUT(gradU.T());

    return
        sqr(this->delta())/12
       *symm
       (
            this->alpha_*rho*(gradUT & gradU)
          + this->alpha_*(U*(gradRho & gradU))
          + this->alpha_*((gradRho & gradU)*U)
          + rho*(U*(gradAlpha & gradU))
          + rho*((gradAlpha & gradU)*U)
          + (U*U)*(gradAlpha & gradRho)
        );
}


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

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

    thresholdGradAlpha_
    (
        "thresholdGradAlpha",
        inv(dimLength),
        this->coeffDict(),
        Zero
    ),

    thresholdGradRho_
    (
        "thresholdGradRho",
        dimDensity/dimLength,
        this->coeffDict(),
        Zero
    ),

    thresholdGradU_
    (
        "thresholdGradU",
        inv(dimTime),
        this->coeffDict(),
        Zero
    )
{}


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

    thresholdGradAlpha_
    (
        "thresholdGradAlpha",
        inv(dimLength),
        this->coeffDict(),
        Zero
    ),

    thresholdGradRho_
    (
        "thresholdGradRho",
        dimDensity/dimLength,
        this->coeffDict(),
        Zero
    ),

    thresholdGradU_
    (
        "thresholdGradU",
        inv(dimTime),
        this->coeffDict(),
        Zero
    )
{}


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

} // End namespace LESModels
} // End namespace Foam

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