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    Copyright (C) 2011-2018 OpenFOAM Foundation
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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
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Class
    Foam::dragModels::WenYu

Description
    Wen and Yu drag model

    Reference:
    \verbatim
        Enwald, H., Peirano, E., & Almstedt, A. E. (1996).
        Eulerian two-phase flow theory applied to fluidization.
        International Journal of Multiphase Flow, 22, 21-66.
        Eq. 86-87, p. 40.
    \endverbatim

SourceFiles
    WenYu.C

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

#ifndef WenYu_H
#define WenYu_H

#include "dragModel.H"

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

namespace Foam
{

class phasePair;

namespace dragModels
{

/*---------------------------------------------------------------------------*\
                           Class WenYu Declaration
\*---------------------------------------------------------------------------*/

class WenYu
:
    public dragModel
{
    // Private data

        //- Residual Reynolds Number
        const dimensionedScalar residualRe_;


public:

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


    // Constructors

        //- Construct from a dictionary and a phase pair
        WenYu
        (
            const dictionary& dict,
            const phasePair& pair,
            const bool registerObject
        );


    //- Destructor
    virtual ~WenYu();


    // Member Functions

        //- Drag coefficient
        virtual tmp<volScalarField> CdRe() const;
};


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

} // End namespace dragModels
} // End namespace Foam

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

#endif

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