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License
    This file is part of OpenFOAM.

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    under the terms of the GNU General Public License as published by
    the Free Software Foundation, either version 3 of the License, or
    (at your option) any later version.

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    You should have received a copy of the GNU General Public License
    along with OpenFOAM.  If not, see <http://www.gnu.org/licenses/>.

Class
    Foam::LESModels::Smagorinsky

Description
    The Smagorinsky SGS model.

    Reference:
    \verbatim
        Smagorinsky, J. (1963).
        General circulation experiments with the primitive equations: I.
        The basic experiment*.
        Monthly weather review, 91(3), 99-164.
    \endverbatim

    The form of the Smagorinsky model implemented is obtained from the
    k-equation model assuming local equilibrium which provides estimates of both
    k and epsilon separate from the sub-grid scale viscosity:

    \verbatim
        B = 2/3*k*I - 2*nuSgs*dev(D)

    where

        D = symm(grad(U));
        k from D:B + Ce*k^3/2/delta = 0
        nuSgs = Ck*sqrt(k)*delta
    \endverbatim

    The default model coefficients are
    \verbatim
        SmagorinskyCoeffs
        {
            Ck                  0.094;
            Ce                  1.048;
        }
    \endverbatim

See also
    Foam::LESModels::kEqn

SourceFiles
    Smagorinsky.C

\*---------------------------------------------------------------------------*/

#ifndef Smagorinsky_H
#define Smagorinsky_H

#include "LESModel.H"
#include "LESeddyViscosity.H"

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

namespace Foam
{
namespace LESModels
{

/*---------------------------------------------------------------------------*\
                           Class Smagorinsky Declaration
\*---------------------------------------------------------------------------*/

template<class BasicMomentumTransportModel>
class Smagorinsky
:
    public LESeddyViscosity<BasicMomentumTransportModel>
{
protected:

    // Protected data

        dimensionedScalar Ck_;


    // Protected Member Functions

        //- Return SGS kinetic energy
        //  calculated from the given velocity gradient
        tmp<volScalarField> k(const tmp<volTensorField>& gradU) const;

        //- Update the SGS eddy viscosity
        virtual void correctNut();


public:

    typedef typename BasicMomentumTransportModel::alphaField alphaField;
    typedef typename BasicMomentumTransportModel::rhoField rhoField;
    typedef typename BasicMomentumTransportModel::transportModel transportModel;


    //- Runtime type information
    TypeName("Smagorinsky");


    // Constructors

        //- Construct from components
        Smagorinsky
        (
            const alphaField& alpha,
            const rhoField& rho,
            const volVectorField& U,
            const surfaceScalarField& alphaRhoPhi,
            const surfaceScalarField& phi,
            const transportModel& transport,
            const word& type = typeName
        );

        //- Disallow default bitwise copy construction
        Smagorinsky(const Smagorinsky&) = delete;


    //- Destructor
    virtual ~Smagorinsky()
    {}


    // Member Functions

        //- Read model coefficients if they have changed
        virtual bool read();

        //- Return SGS kinetic energy
        virtual tmp<volScalarField> k() const
        {
            return k(fvc::grad(this->U_));
        }

        //- Return sub-grid disipation rate
        virtual tmp<volScalarField> epsilon() const;

        //- Correct Eddy-Viscosity and related properties
        virtual void correct();


    // Member Operators

        //- Disallow default bitwise assignment
        void operator=(const Smagorinsky&) = delete;
};


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

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

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

#ifdef NoRepository
    #include "Smagorinsky.C"
#endif

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

#endif

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