powerLaw.C

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#include "powerLaw.H"
#include "volFields.H"
#include "addToRunTimeSelectionTable.H"

// * * * * * * * * * * * * * * Static Data Members * * * * * * * * * * * * * //

namespace Foam
{
namespace laminarModels
{
namespace generalisedNewtonianViscosityModels
{
    defineTypeNameAndDebug(powerLaw, 0);

    addToRunTimeSelectionTable
    (
        generalisedNewtonianViscosityModel,
        powerLaw,
        dictionary
    );
}
}
}


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

Foam::laminarModels::generalisedNewtonianViscosityModels::powerLaw::powerLaw
(
    const dictionary& viscosityProperties
)
:
    generalisedNewtonianViscosityModel(viscosityProperties),
    k_("k", dimViscosity, 0),
    n_("n", dimless, 0),
    nuMin_("nuMin", dimViscosity, 0),
    nuMax_("nuMax", dimViscosity, 0)
{
    read(viscosityProperties);
}


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

bool Foam::laminarModels::generalisedNewtonianViscosityModels::powerLaw::read
(
    const dictionary& viscosityProperties
)
{
    generalisedNewtonianViscosityModel::read(viscosityProperties);

    const dictionary& coeffs =
        viscosityProperties.optionalSubDict(typeName + "Coeffs");

    coeffs.lookup("k") >> k_;
    coeffs.lookup("n") >> n_;
    coeffs.lookup("nuMin") >> nuMin_;
    coeffs.lookup("nuMax") >> nuMax_;

    return true;
}


Foam::tmp<Foam::volScalarField>
Foam::laminarModels::generalisedNewtonianViscosityModels::powerLaw::
nu
(
    const volScalarField& nu0,
    const volScalarField& strainRate
) const
{
    return max
    (
        nuMin_,
        min
        (
            nuMax_,
            k_*pow
            (
                max
                (
                    dimensionedScalar(dimTime, 1.0)*strainRate,
                    dimensionedScalar(dimless, small)
                ),
                n_.value() - scalar(1)
            )
        )
    );
}


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