fractal.C

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#include "fractal.H"
#include "addToRunTimeSelectionTable.H"
#include "sinteringModel.H"
#include "fvmDdt.H"
#include "fvmDiv.H"
#include "fvmSup.H"
#include "mixedFvPatchField.H"
 
using Foam::constant::mathematical::pi;
 
// * * * * * * * * * * * * * * Static Data Members * * * * * * * * * * * * * //
 
namespace Foam
{
namespace diameterModels
{
namespace shapeModels
{
    defineTypeNameAndDebug(fractal, 0);
    addToRunTimeSelectionTable(shapeModel, fractal, dictionary);
}
}
}
 
template<>
const char*
Foam::NamedEnum
<
    Foam::diameterModels::shapeModels::fractal::surfaceGrowthTypes,
    3
>::names[] = {"hardSphere", "ParkRogak", "conserved"};
 
const Foam::NamedEnum
<
    Foam::diameterModels::shapeModels::fractal::surfaceGrowthTypes,
    3
> Foam::diameterModels::shapeModels::fractal::sgTypeNames_;
 
 
// * * * * * * * * * * * * Private Member Functions  * * * * * * * * * * * * //
 
Foam::tmp<Foam::volScalarField>
Foam::diameterModels::shapeModels::fractal::dColl() const
{
    tmp<volScalarField> tDColl
    (
        volScalarField::New
        (
            "dColl",
            group().mesh(),
            dimensionedScalar(dimLength, Zero)
        )
    );
 
    volScalarField& dColl = tDColl.ref();
 
    dColl =
        6/kappa_
       *pow(group().x()*pow3(kappa_)/(36*pi*alphaC_), 1/Df_);
 
    return tDColl;
}
 
 
// * * * * * * * * * * * * * * * * Constructors  * * * * * * * * * * * * * * //
 
Foam::diameterModels::shapeModels::fractal::fractal
(
    const dictionary& dict,
    const sizeGroup& group,
    const dictionary& groupDict
)
:
    SecondaryPropertyModel<shapeModel>(group),
    kappa_
    (
        sizeGroup::fieldIo("kappa", group.i(), group.group()),
        sizeGroup::field("kappa", group.i(), group.group())
    ),
    Df_("Df", dimless, groupDict),
    alphaC_("alphaC", dimless, groupDict),
    dColl_
    (
        IOobject
        (
            "dColl" + group.name().substr(1),
            group.mesh().time().name(),
            group.mesh()
        ),
        this->dColl()
    ),
    Su_
    (
        IOobject
        (
            IOobject::groupName("Su", kappa_.name()),
            group.mesh().time().name(),
            group.mesh()
        ),
        group.mesh(),
        dimensionedScalar(kappa_.dimensions()/dimTime, Zero)
    ),
    sinteringModel_(sinteringModel::New(dict.subDict(type() + "Coeffs"), *this))
{
    // Check and filter for old syntax (remove in due course)
    if (groupDict.found("kappa"))
    {
        FatalErrorInFunction
            << "A 'kappa' entry should not be specified for size-group #"
            << group.i() << " of population balance "
            << group.group().popBalName()
            << ". Instead, the value should be initialised within the field, "
            << this->name() << " (or the default field, "
            << IOobject::groupName("kappaDefault", group.phase().name())
            << ", as appropriate)."
            << exit(FatalError);
    }
}
 
 
// * * * * * * * * * * * * * * * * Destructor  * * * * * * * * * * * * * * * //
 
Foam::diameterModels::shapeModels::fractal::~fractal()
{}
 
 
// * * * * * * * * * * * * * * * Member Functions  * * * * * * * * * * * * * //
 
const Foam::volScalarField&
Foam::diameterModels::shapeModels::fractal::fld() const
{
    return kappa_;
}
 
 
Foam::volScalarField&
Foam::diameterModels::shapeModels::fractal::src()
{
    return Su_;
}
 
 
void Foam::diameterModels::shapeModels::fractal::correct()
{
    const sizeGroup& fi = group();
    const phaseModel& phase = fi.phase();
    const volScalarField& alpha = phase;
 
    const populationBalanceModel& popBal =
        group().mesh().lookupObject<populationBalanceModel>
        (
            group().group().popBalName()
        );
 
    surfaceScalarField fAlphaPhi
    (
        "fAlphaPhi",
        max(fvc::interpolate(fi, "fi"), small)*phase.alphaPhi()
    );
 
    fvScalarMatrix kappaEqn
    (
        fvm::ddt(alpha, fi, kappa_)
      + fvm::div(fAlphaPhi, kappa_)
      ==
      - sinteringModel_->R()
      + Su_
      - fvm::Sp(popBal.Sp(fi.i())*fi, kappa_)
      - correction
        (
            fvm::Sp
            (
                max(phase.residualAlpha() - alpha*fi, scalar(0))
               /group().mesh().time().deltaT(),
                kappa_
            )
        )
    );
 
    kappaEqn.relax();
 
    kappaEqn.solve();
 
    // Bounding of kappa assuming first sizeGroup to represent one primary
    // particle
    kappa_ =
        min
        (
            max(kappa_, 6/group().dSph()),
            6/popBal.sizeGroups().first().dSph()
        );
 
    kappa_.correctBoundaryConditions();
 
    // Update the collisional diameter
    dColl_ = dColl();
}
 
 
const Foam::tmp<Foam::volScalarField>
Foam::diameterModels::shapeModels::fractal::a() const
{
    return kappa_*group().x();
}
 
 
void Foam::diameterModels::shapeModels::fractal::addDrift
(
    const volScalarField &Su,
    const sizeGroup &fu,
    const driftModel &model
)
{
    surfaceGrowthTypes sgType
    (
        sgTypeNames_.read
        (
            model.dict().lookup("surfaceGrowthType")
        )
    );
 
    const volScalarField& sourceKappa =
        SecondaryPropertyModelTable()[SecondaryPropertyName(fu)]->fld();
 
    switch (sgType)
    {
        case sgHardSphere:
        {
            Su_ += sourceKappa*fu.dSph()/group().dSph()*Su;
 
            break;
        }
 
        case sgParkRogak:
        {
            const fractal& sourceShape =
                refCast<const fractal>
                (
                    fu.shapeModelPtr()()
                );
 
            volScalarField dp(6/sourceKappa);
            const volScalarField a(sourceKappa*fu.x());
            const dimensionedScalar dv(group().x() - fu.x());
 
            const volScalarField da1
            (
                (2.0/3.0)*dv
               *(
                    sourceKappa
                  + sourceShape.Df_*(1/sourceShape.d() - 1/dp)
                )
            );
 
            dp += 6*(dv*a - fu.x()*da1)/sqr(a);
 
            const volScalarField np(6*group().x()/pi/pow3(dp));
            const volScalarField dc(dp*pow(np/alphaC_, 1/Df_));
 
            const volScalarField da2
            (
                dv*(4/dp + 2*Df_/3*(1/dc - 1/dp))
            );
 
            Su_ += (a + 0.5*da1 + 0.5*da2)/group().x()*Su;
 
            break;
        }
 
        case sgConserved:
        {
            SecondaryPropertyModel::addDrift(Su, fu, model);
 
            break;
        }
 
        default:
        {
            FatalErrorInFunction
                << "Unknown surface growth type. Valid types are:"
                << sgTypeNames_ << nl << exit(FatalError);
        }
    }
}
 
 
// ************************************************************************* //