/*---------------------------------------------------------------------------*\
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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::fv::constant

Description
    Test entrainment model: pairContinuous is converted to pairDisperse at a
    given constant area-specific mass flow rate (entrainmentRate).

    The transfer is distributed over the interface, i.e. in cells with nonzero
    values of the interfacial area density \f$||\nabla\alpha||\f$ (IAD). Such a
    cell can only contribute to the transfer if it contains some pairContinuous.
    If not, the corresponding proportion of IAD is approximately added to a
    neighbour cell still containing pairContinuous to realise the whole transfer
    rate.

Usage
    \table
        Property    | Description                          | Required | Default
        threshold   | Minimum entraining phase fraction    | no       | 0.2
        entrainmentRate| Constant entrainment rate         | no       | 1
    \endtable

SourceFiles
    constant.C

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

#ifndef constant_H
#define constant_H

#include "entrainmentModel.H"

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

namespace Foam
{

namespace fv
{

/*---------------------------------------------------------------------------*\
                          Class constant Declaration
\*---------------------------------------------------------------------------*/

class constant
:
    public entrainmentModel
{
    // Private Data

        //- Entrainment rate
        const dimensionedScalar entrainmentRate_;


protected:

    // Protected Member Functions

        //- Returns the mass transfer rate
        virtual tmp<volScalarField> rate(const phaseModel&) const;


public:

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


    // Constructors

        //- Construct from components
        constant
        (
            const dictionary& dict,
            const dispersedPhaseInterface& interface
        );


    //- Destructor
    virtual ~constant();
};


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

} // End namespace fv
} // End namespace Foam

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

#endif

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