/*---------------------------------------------------------------------------*\
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                    \\     ||  | Multiphase Code Repository by HZDR
  ======   //   ||  || ===//   | Website: https://doi.org/10.14278/rodare.767
  ||  ||  //    ||  // || \\   | License: GPL-3.0-or-later
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-------------------------------------------------------------------------------
License
    This file is part of the Multiphase Code Repository by HZDR.

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    Website: https://hzdr.de

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Class
    Foam::dragModels::Zhao

Description
    Solid-solid drag model which accounts for the momentum transfer between
    distinct particulate phases in dense regime. Note that the Stokes law
    coefficient zeta can be determined via Eq. (39) in Zhao et al. (2023) for a
    varying total solid concentration.

    Reference:
    \verbatim
    Junnan Zhao , Guodong Liu, Xinyao Guo , Huilin Lu (2023)
    A modified stokes law-based solid-solid drag model for
    the gas-fluidization of binary mixtures with different sizes
    and densities.
    Powder Technology, 425, 118533.
    https://doi.org/10.1016/j.powtec.2023.118533
    \endverbatim

Usage
    \table
        Property | Description            | Required | Default value
        zeta     | Stokes law coefficient | yes      | -
    \endtable

    Example usage:
    \verbatim
    solid1_solid2
    {
        type            Zhao;

        zeta            1;
    }
    \endverbatim

SourceFiles
    Zhao.C

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

#ifndef Zhao_H
#define Zhao_H

#include "dragModel.H"

namespace Foam
{
namespace dragModels
{

/*---------------------------------------------------------------------------*\
                       Class Modified Stokes Declaration
\*---------------------------------------------------------------------------*/
class Zhao
:
    public dragModel
{
    // Private Data

        //- Interface
        const phaseInterface interface_;

        //- Stokes law coefficient
        const dimensionedScalar zeta_;

public:

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


    // Constructors

        //- Construct from a dictionary and an interface
        Zhao
        (
            const dictionary& dict,
            const phaseInterface& interface,
            const bool registerObject
        );


    //- Destructor
    virtual ~Zhao();


    // Member Functions

        //- The drag coefficient used in the momentum equation
        virtual tmp<volScalarField> K() const;

        //- The drag coefficient used in the face-momentum equations
        virtual tmp<surfaceScalarField> Kf() const;

};

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

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

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

#endif

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