freePiston.H

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/*---------------------------------------------------------------------------*\
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-------------------------------------------------------------------------------
    Copyright (C) 2017 OpenFOAM Foundation
-------------------------------------------------------------------------------
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::freePiston
 
Description
    In case of free pistons, the piston position is determined by a user-defined
    position according to time.
 
    The piston trajectory is specified in \c constant/engineGeometry using a
    table or a separated file. The position is relative to the cylinder head,
    i.e. decreasing when compressing.
 
    For example,
    \verbatim
        pistonPositionTime  table ((0 0.13) (0.020 0.03));
    \endverbatim
    or
    \verbatim
        pistonPositionTime
        {
            type    table;
            file    "<constant>/pistonPosition.dat";
            outOfBounds         clamp;
            interpolationScheme linear;
        }
    \endverbatim
 
SourceFiles
    freePiston.C
 
\*---------------------------------------------------------------------------*/
 
#ifndef freePiston_H
#define freePiston_H
 
#include "engineTime.H"
#include "dictionary.H"
#include "dimensionedScalar.H"
#include "Function1.H"
 
// * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * //
 
namespace Foam
{
 
/*---------------------------------------------------------------------------*\
                        Class freePiston Declaration
\*---------------------------------------------------------------------------*/
 
class freePiston
:
    public engineTime
{
    // Private Data
 
        autoPtr<Function1<scalar>> pistonPositionTime_;
 
 
    // Private Member Functions
 
        //- No copy construct
        freePiston(const freePiston&) = delete;
 
        //- No copy assignment
        void operator=(const freePiston&) = delete;
 
 
public:
 
    //- Runtime type information
    TypeName("freePiston");
 
 
    // Constructors
 
        //- Construct from objectRegistry arguments
        freePiston
        (
            const word& name,
            const fileName& rootPath,
            const fileName& caseName,
            const fileName& systemName = "system",
            const fileName& constantName = "constant",
            const fileName& dictName = "engineGeometry"
        );
 
    //- Destructor
    virtual ~freePiston() = default;
 
 
    // Member Functions
 
        // Conversion
 
            //- Calculate the piston position from the engine geometry
            //  and given crank angle.
            scalar pistonPosition(const scalar theta) const;
 
 
        // Access
 
            //- Return current engine time
            virtual scalar theta() const;
 
            //- Return time unit
            virtual word unit() const;
 
            //- Return engine time increment
            virtual scalar deltaTheta() const;
};
 
 
// * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * //
 
} // End namespace Foam
 
// * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * //
 
#endif
 
// ************************************************************************* //