svenssonHaggkvistCanopySource.H

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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.
 
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    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/>.
 
    Copyright is held by the author.
 
Class
    Foam::fv::svenssonHaggkvistCanopySource
 
Group
    grpFvOptionsSources
 
Author
    David Segersson, Swedish Meteorological and Hydrological Institute
    david.segersson@smhi.se
 
Description
    Momentum and turbulence source/sink-terms for tree canopy according to Svensson & Häggkvist (1990), with parameters adjusted according t    o Mochida et al. (2008).
    
    Momentum source term is expressed as:
        \f[
            S_u = -\rho C_d \alpha u^2
        \f]
 
    Source term for k is expressed as:
 
        \f[
            S_k = \rho C_d \alpha u^3
        \f]
 
    Source term for epsilon is expressed as:
 
        \f[
            S_{\epsilon} = \rho C_d \alpha C_{p \epsilon 1} \frac{\epsilon}{k} u^3 
        \f]
 
    where
    
    \vartable
        \rho             | density
        u                | magnitude of velocity
        k                | turbulent kinetic energy
        \alpha           | leaf area density [m]
        C_d              | tree canopy drag coefficient
        C_{p \epsilon 1} | coefficient with value 1.8 (Mochida et al. 2008)
    \endvartable
 
    Use with any variant of the k-\epsilon turbulence model.
    
 
    Reference:
        Mochida A., Tabata Y., Iwata T., Yoshino H., Examining tree canopy models for CFD prediction
        of wind environment at pedestrian level, J. Wind Eng. Ind.
        Aerodyn. 96 (2008) 1667-1677.
    
        Svensson, U., Häggkvist, K. A two-equation turbulence model for canopy flows. J. Wind Eng. Ind.
        Aerodyn. 35 (1990) 201–211.
    
Usage
    Example usage:
    \verbatim
    SBM
    {
        type            svenssonHaggkvistCanopySource;
        active          on;
    }
    \endverbatim
 
SourceFiles
    svenssonHaggkvistCanopySource.C
 
\*---------------------------------------------------------------------------*/
 
#ifndef svenssonHaggkvistCanopySource_H
#define svenssonHaggkvistCanopySource_H
 
#include "fvOption.H"
#include "dimensionedTypes.H"
#include "wallFvPatch.H"
#include "canopySource.H"
 
// * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * //
 
namespace Foam
{
namespace fv
{
 
/*---------------------------------------------------------------------------*\
                 Class svenssonHaggkvistCanopySource Declaration
\*---------------------------------------------------------------------------*/
 
class svenssonHaggkvistCanopySource
:
    public canopySource
{
private:
 
        // Canopy coefficients
        dimensionedScalar CpEps1_;
  
        //- Disallow default bitwise copy construct
        svenssonHaggkvistCanopySource(const svenssonHaggkvistCanopySource&);
 
        //- Disallow default bitwise assignment
        void operator=(const svenssonHaggkvistCanopySource&);
 
 
        //- Source term to momentum equation
        template<class RhoFieldType>
        void addSup
        (
            const RhoFieldType& rho,
            fvMatrix<vector>& eqn,
            const label fieldi
        );
 
        template<class RhoFieldType>
        void addSup
        (
            const RhoFieldType& rho,
            fvMatrix<scalar>& eqn,
            const label fieldi
        );
 
 
        // Private Member Functions
 
  
public:
 
 
    //- Runtime type information
    TypeName("svenssonHaggkvistCanopySource");
 
 
    // Constructors
 
        //- Construct from components
        svenssonHaggkvistCanopySource
        (
            const word& name,
            const word& modelType,
            const dictionary& dict,
            const fvMesh& mesh
        );
 
 
    //- Destructor
    virtual ~svenssonHaggkvistCanopySource()
    {}
 
 
    // Member Functions
        // access
 
       dimensionedScalar CpEps1() const
        {
            return CpEps1_;
        }
 
        //- Source term to momentum equation
        void addSup
        (
            fvMatrix<vector>& eqn,
            const label fieldi
        );
 
        //- Source term to scalar equations (k & epsilon)
        void addSup
        (
            fvMatrix<scalar>& eqn,
            const label fieldi
        );
 
 
        //- Source term to compressible momentum equation
        void addSup
        (
            const volScalarField& rho,
            fvMatrix<vector>& eqn,
            const label fieldi
        );
 
        //- Source term to compressible scalar equation (k & epsilon)
        void addSup
        (
            const volScalarField& rho,
            fvMatrix<scalar>& eqn,
            const label fieldi
        );
 
};
 
 
// * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * //
 
} // End namespace fv
} // End namespace Foam
 
// * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * //
 
#endif
 
// ************************************************************************* //