SphereDragForce.H

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    Copyright (C) 2011-2017 OpenFOAM Foundation
    Copyright (C) 2021 OpenCFD Ltd.
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License
    This file is part of OpenFOAM.
 
    OpenFOAM is free software: you can redistribute it and/or modify it
    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.
 
    OpenFOAM is distributed in the hope that it will be useful, but WITHOUT
    ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or
    FITNESS FOR A PARTICULAR PURPOSE.  See the GNU General Public License
    for more details.
 
    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::SphereDragForce
 
Group
    grpLagrangianIntermediateForceSubModels
 
Description
    Particle-drag model wherein drag forces (per unit carrier-fluid
    velocity) are dynamically computed based on empirical expressions.
 
    \f[
        \mathrm{F}_\mathrm{D} =
            \frac{3}{4}
            \frac{\mu_c\,\mathrm{C}_\mathrm{D}\,\mathrm{Re}_p}{\rho_p \, d_p^2}
    \f]
    with
 
    \f[
        \mathrm{C}_\mathrm{D} =
            \frac{24}{\mathrm{Re}_p}
            \left(1 + \frac{1}{6}\mathrm{Re}_p^{2/3} \right)
            \quad \mathrm{if} \quad \mathrm{Re}_p \leq 1000
    \f]
    \f[
        \mathrm{C}_\mathrm{D} =
            0.424 \quad \mathrm{if} \quad \mathrm{Re}_p > 1000
    \f]
    and
    \f[
        \mathrm{Re}_p =
            \frac{\rho_c \, | \mathbf{u}_\mathrm{rel} | \, d_p}{\mu_c}
    \f]
 
    where
    \vartable
        \mathrm{F}_\mathrm{D} | Drag force per carrier-fluid velocity [kg/s]
        \mathrm{C}_\mathrm{D} | Particle drag coefficient
        \mathrm{Re}_p         | Particle Reynolds number
        \rho_p                | Particle mass density
        \mu_c    | Dynamic viscosity of carrier at the cell occupying particle
        d_p                   | Particle diameter
        \rho_c   | Density of carrier at the cell occupying particle
        \mathbf{u}_\mathrm{rel} | Relative velocity between particle and carrier
    \endvartable
 
    Constraints:
    - Particles remain spherical throughout the force
    computation, hence no particle distortion.
    - Applicable to particles with a spatially homogeneous distribution.
 
    References:
    \verbatim
        Standard model:
            Putnam, A. (1961).
            Integratable form of droplet drag coefficient.
            ARS Journal, 31(10), 1467-1468.
 
        Expressions (tag:AOB), (Eq. 34-35):
            Amsden, A. A., O'Rourke, P. J., & Butler, T. D. (1989).
            KIVA-II: A computer program for chemically
            reactive flows with sprays (No. LA-11560-MS).
            Los Alamos National Lab.(LANL), Los Alamos, NM (United States).
            DOI:10.2172/6228444
    \endverbatim
 
Usage
    Minimal example by using \c constant/<CloudProperties>:
    \verbatim
    subModels
    {
        particleForces
        {
            sphereDrag;
        }
    }
    \endverbatim
 
    where the entries mean:
    \table
      Property     | Description                       | Type | Reqd | Deflt
      type         | Type name: sphereDrag             | word | yes  | -
    \endtable
 
Note
  - \f$\mathrm{F}_\mathrm{D}\f$ is weighted with the particle mass/density
    at the stage of a function return, so that it can later be normalised
    with the effective mass, if necessary (e.g. when using virtual-mass forces).
 
SourceFiles
    SphereDragForce.C
 
\*---------------------------------------------------------------------------*/
 
#ifndef SphereDragForce_H
#define SphereDragForce_H
 
#include "ParticleForce.H"
 
// * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * //
 
namespace Foam
{
/*---------------------------------------------------------------------------*\
                       Class SphereDragForce Declaration
\*---------------------------------------------------------------------------*/
 
template<class CloudType>
class SphereDragForce
:
    public ParticleForce<CloudType>
{
    // Private Member Functions
 
        //- Drag coefficient multiplied by Reynolds number
        scalar CdRe(const scalar Re) const;
 
 
public:
 
    //- Runtime type information
    TypeName("sphereDrag");
 
 
    // Constructors
 
        //- Construct from mesh
        SphereDragForce
        (
            CloudType& owner,
            const fvMesh& mesh,
            const dictionary& dict
        );
 
        //- Construct copy
        SphereDragForce(const SphereDragForce<CloudType>& df);
 
        //- Construct and return a clone
        virtual autoPtr<ParticleForce<CloudType>> clone() const
        {
            return autoPtr<ParticleForce<CloudType>>
            (
                new SphereDragForce<CloudType>(*this)
            );
        }
 
        //- No copy assignment
        void operator=(const SphereDragForce<CloudType>&) = delete;
 
 
    //- Destructor
    virtual ~SphereDragForce() = default;
 
 
    // Member Functions
 
        // Evaluation
 
            //- Calculate the coupled force
            virtual forceSuSp calcCoupled
            (
                const typename CloudType::parcelType& p,
                const typename CloudType::parcelType::trackingData& td,
                const scalar dt,
                const scalar mass,
                const scalar Re,
                const scalar muc
            ) const;
};
 
 
// * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * //
 
} // End namespace Foam
 
// * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * //
 
#ifdef NoRepository
    #include "SphereDragForce.C"
#endif
 
// * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * //
 
#endif
 
// ************************************************************************* //