Q.H

Go to the documentation of this file.

/*---------------------------------------------------------------------------*\
  =========                 |
  \\      /  F ield         | OpenFOAM: The Open Source CFD Toolbox
   \\    /   O peration     | Website:  https://openfoam.org
    \\  /    A nd           | Copyright (C) 2013-2025 OpenFOAM Foundation
     \\/     M anipulation  |
-------------------------------------------------------------------------------
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::functionObjects::Q
 
Description
    Calculates and outputs the second invariant of the velocity gradient tensor
    [1/s^2].
 
    \f[
        Q = 0.5(sqr(tr(\nabla U)) - tr(((\nabla U) \cdot (\nabla U))))
    \f]
 
See also
    Foam::functionObjects::fieldExpression
    Foam::functionObjects::fvMeshFunctionObject
 
SourceFiles
    Q.C
 
\*---------------------------------------------------------------------------*/
 
#ifndef Q_functionObject_H
#define Q_functionObject_H
 
#include "fieldExpression.H"
 
// * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * //
 
namespace Foam
{
namespace functionObjects
{
 
/*---------------------------------------------------------------------------*\
                              Class Q Declaration
\*---------------------------------------------------------------------------*/
 
class Q
:
    public fieldExpression
{
    // Private Member Functions
 
        //- Calculate the Q field and return true if successful
        virtual bool calc();
 
 
public:
 
    //- Runtime type information
    TypeName("Q");
 
 
    // Constructors
 
        //- Construct from Time and dictionary
        Q
        (
            const word& name,
            const Time& runTime,
            const dictionary& dict
        );
 
 
    //- Destructor
    virtual ~Q();
};
 
 
// * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * //
 
} // End namespace functionObjects
} // End namespace Foam
 
// * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * //
 
#endif
 
// ************************************************************************* //