HerschelBulkley.C

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#include "HerschelBulkley.H"
#include "volFields.H"
#include "addToRunTimeSelectionTable.H"
 
// * * * * * * * * * * * * * * Static Data Members * * * * * * * * * * * * * //
 
namespace Foam
{
namespace laminarModels
{
namespace generalizedNewtonianViscosityModels
{
    defineTypeNameAndDebug(HerschelBulkley, 0);
 
    addToRunTimeSelectionTable
    (
        generalizedNewtonianViscosityModel,
        HerschelBulkley,
        dictionary
    );
}
}
}
 
 
// * * * * * * * * * * * * * * * * Constructors  * * * * * * * * * * * * * * //
 
Foam::laminarModels::generalizedNewtonianViscosityModels::HerschelBulkley::
HerschelBulkley
(
    const dictionary& viscosityProperties
)
:
    generalizedNewtonianViscosityModel(viscosityProperties),
    HerschelBulkleyCoeffs_
    (
        viscosityProperties.optionalSubDict(typeName + "Coeffs")
    ),
    n_("n", dimless, HerschelBulkleyCoeffs_),
    tau0_("tau0", dimViscosity/dimTime, HerschelBulkleyCoeffs_)
{}
 
 
// * * * * * * * * * * * * * * Member Functions  * * * * * * * * * * * * * * //
 
bool Foam::laminarModels::generalizedNewtonianViscosityModels::
HerschelBulkley::read
(
    const dictionary& viscosityProperties
)
{
    generalizedNewtonianViscosityModel::read(viscosityProperties);
 
    HerschelBulkleyCoeffs_ =
        viscosityProperties.optionalSubDict(typeName + "Coeffs");
 
    HerschelBulkleyCoeffs_.readEntry("n", n_);
    HerschelBulkleyCoeffs_.readEntry("tau0", tau0_);
 
    return true;
}
 
 
Foam::tmp<Foam::volScalarField>
Foam::laminarModels::generalizedNewtonianViscosityModels::HerschelBulkley::
nu
(
    const volScalarField& nu0,
    const volScalarField& strainRate
) const
{
    const dimensionedScalar tone("tone", dimTime, 1);
    const dimensionedScalar rtone("rtone", dimless/dimTime, 1);
 
    return
    (
        min
        (
            nu0,
            (tau0_ + nu0*rtone*pow(tone*strainRate, n_))
           /max
            (
                strainRate,
                dimensionedScalar("SMALL", dimless/dimTime, VSMALL)
            )
        )
    );
}
 
 
// ************************************************************************* //