kineticGasEvaporation.C

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  \\      /  F ield         | OpenFOAM: The Open Source CFD Toolbox
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    Copyright (C) 2017-2020 OpenCFD Ltd.
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License
    This file is part of OpenFOAM.
 
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    the Free Software Foundation, either version 3 of the License, or
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    FITNESS FOR A PARTICULAR PURPOSE.  See the GNU General Public License
    for more details.
 
    You should have received a copy of the GNU General Public License
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#include "kineticGasEvaporation.H"
#include "constants.H"
#include "cutCellIso.H"
#include "volPointInterpolation.H"
#include "wallPolyPatch.H"
#include "fvcSmooth.H"
 
using namespace Foam::constant;
 
 
// * * * * * * * * * * *  Private Member Functions * * * * * * * * * * * * * //
 
template<class Thermo, class OtherThermo>
void Foam::meltingEvaporationModels::kineticGasEvaporation<Thermo, OtherThermo>
::updateInterface(const volScalarField& T)
{
    const fvMesh& mesh = this->mesh_;
 
    const volScalarField& alpha = this->pair().from();
 
    scalarField ap
    (
        volPointInterpolation::New(mesh).interpolate(alpha)
    );
 
    cutCellIso cutCell(mesh, ap);
 
    forAll(interfaceArea_, celli)
    {
        label status = cutCell.calcSubCell(celli, isoAlpha_);
        interfaceArea_[celli] = 0;
        if (status == 0) // cell is cut
        {
            interfaceArea_[celli] =
                mag(cutCell.faceArea())/mesh.V()[celli];
        }
    }
 
    for (const polyPatch& pp : mesh.boundaryMesh())
    {
        if (isA<wallPolyPatch>(pp))
        {
            forAll(pp.faceCells(), faceI)
            {
                const label pCelli = pp.faceCells()[faceI];
                bool interface(false);
                if
                (
                     sign(C_.value()) > 0
                 && (T[pCelli] - Tactivate_.value()) > 0
                )
                {
                    interface = true;
                }
 
                if
                (
                    sign(C_.value()) < 0
                 && (T[pCelli] - Tactivate_.value()) < 0
                )
                {
                    interface = true;
                }
 
                if
                (
                    interface
                 &&
                    (
                        alpha[pCelli] < 2*isoAlpha_
                     && alpha[pCelli] > 0.5*isoAlpha_
                    )
                )
                {
                    interfaceArea_[pCelli] =
                        mag(pp.faceAreas()[faceI])/mesh.V()[pCelli];
                }
            }
        }
    }
}
 
 
// * * * * * * * * * * * * * * * * Constructors  * * * * * * * * * * * * * * //
 
template<class Thermo, class OtherThermo>
Foam::meltingEvaporationModels::kineticGasEvaporation<Thermo, OtherThermo>
::kineticGasEvaporation
(
    const dictionary& dict,
    const phasePair& pair
)
:
    InterfaceCompositionModel<Thermo, OtherThermo>(dict, pair),
    C_("C", dimless, dict),
    Tactivate_("Tactivate", dimTemperature, dict),
    Mv_("Mv", dimMass/dimMoles, -1, dict),
    interfaceArea_
    (
        IOobject
        (
            "interfaceArea",
            this->mesh_.time().timeName(),
            this->mesh_,
            IOobject::NO_READ,
            IOobject::NO_WRITE
        ),
        this->mesh_,
        dimensionedScalar(dimless/dimLength, Zero)
    ),
    htc_
    (
        IOobject
        (
            "htc",
            this->mesh_.time().timeName(),
            this->mesh_,
            IOobject::NO_READ,
            IOobject::NO_WRITE
        ),
        this->mesh_,
        dimensionedScalar(dimMass/dimArea/dimTemperature/dimTime, Zero)
    ),
    mDotc_
    (
        IOobject
        (
            "mDotc",
            this->mesh_.time().timeName(),
            this->mesh_,
            IOobject::NO_READ,
            IOobject::AUTO_WRITE
        ),
        this->mesh_,
        dimensionedScalar(dimDensity/dimTime, Zero)
    ),
    isoAlpha_(dict.getOrDefault<scalar>("isoAlpha", 0.5))
{
    word speciesName = IOobject::member(this->transferSpecie());
 
    // Get the "to" thermo
    const typename OtherThermo::thermoType& toThermo =
        this->getLocalThermo
        (
            speciesName,
            this->toThermo_
        );
 
    // Convert from g/mol to Kg/mol
    Mv_.value() = toThermo.W()*1e-3;
 
    if (Mv_.value() == -1)
    {
        FatalErrorInFunction
            << " Please provide the molar weight (Mv) of vapour [g/mol] "
            << abort(FatalError);
    }
}
 
 
// * * * * * * * * * * * * * * Member Functions  * * * * * * * * * * * * * * //
 
template<class Thermo, class OtherThermo>
Foam::tmp<Foam::volScalarField>
Foam::meltingEvaporationModels::kineticGasEvaporation<Thermo, OtherThermo>
::Kexp(const volScalarField& T)
{
 
    const fvMesh& mesh = this->mesh_;
 
    const dimensionedScalar HerztKnudsConst
    (
        sqrt
        (
            2.0*mathematical::pi
          * pow3(Tactivate_)
          * constant::physicoChemical::R/Mv_
        )
    );
 
    word speciesName = IOobject::member(this->transferSpecie());
    tmp<volScalarField> L = this->L(speciesName, T);
 
    updateInterface(T);
 
    tmp<volScalarField> tRhov
    (
        new volScalarField
        (
            IOobject
            (
                "tRhov",
                mesh.time().timeName(),
                mesh
            ),
            mesh,
            dimensionedScalar(dimDensity, Zero)
        )
    );
    volScalarField& rhov = tRhov.ref();
 
    tmp<volScalarField> tdeltaT
    (
        new volScalarField
        (
            IOobject
            (
                "tdeltaT",
                mesh.time().timeName(),
                mesh
            ),
            mesh,
            dimensionedScalar(dimTemperature, Zero)
        )
    );
    volScalarField& deltaT = tdeltaT.ref();
 
    dimensionedScalar T0("T0", dimTemperature, Zero);
 
    if (sign(C_.value()) > 0)
    {
        rhov = this->pair().to().rho();
        deltaT = max(T - Tactivate_, T0);
    }
    else
    {
        rhov = this->pair().from().rho();
        deltaT = max(Tactivate_ - T, T0);
    }
 
    htc_ = 2*mag(C_)/(2-mag(C_))*(L()*rhov/HerztKnudsConst);
 
    mDotc_ = htc_*deltaT*interfaceArea_;
 
    return tmp<volScalarField>(new volScalarField(mDotc_));
}
 
 
template<class Thermo, class OtherThermo>
Foam::tmp<Foam::volScalarField>
Foam::meltingEvaporationModels::kineticGasEvaporation<Thermo, OtherThermo>::KSp
(
    label variable,
    const volScalarField& refValue
)
{
    if (this->modelVariable_ == variable)
    {
        const volScalarField coeff(htc_*interfaceArea_);
 
        if (sign(C_.value()) > 0)
        {
            return(coeff*pos(refValue - Tactivate_));
        }
        else
        {
            return(coeff*pos(Tactivate_ - refValue));
        }
    }
    else
    {
        return tmp<volScalarField> ();
    }
}
 
 
template<class Thermo, class OtherThermo>
Foam::tmp<Foam::volScalarField>
Foam::meltingEvaporationModels::kineticGasEvaporation<Thermo, OtherThermo>::KSu
(
    label variable,
    const volScalarField& refValue
)
{
    if (this->modelVariable_ == variable)
    {
        const volScalarField coeff(htc_*interfaceArea_*Tactivate_);
 
        if (sign(C_.value()) > 0)
        {
            return(-coeff*pos(refValue - Tactivate_));
        }
        else
        {
            return(coeff*pos(Tactivate_ - refValue));
        }
    }
    else
    {
        return tmp<volScalarField> ();
    }
}
 
 
template<class Thermo, class OtherThermo>
const Foam::dimensionedScalar&
Foam::meltingEvaporationModels::kineticGasEvaporation<Thermo, OtherThermo>
::Tactivate() const
{
    return Tactivate_;
}
 
 
template<class Thermo, class OtherThermo>
bool
Foam::meltingEvaporationModels::
kineticGasEvaporation<Thermo, OtherThermo>::includeDivU()
{
    return true;
}
 
// ************************************************************************* //