116 lines
3.2 KiB
C
116 lines
3.2 KiB
C
/*---------------------------------------------------------------------------* \
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========= |
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\\ / F ield | OpenFOAM: The Open Source CFD Toolbox
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\\ / O peration |
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\\ / A nd | Copyright (C) 2011-2012 OpenFOAM Foundation
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\\/ M anipulation |
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-------------------------------------------------------------------------------
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License
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This file is part of OpenFOAM.
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OpenFOAM is free software: you can redistribute it and/or modify it
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under the terms of the GNU General Public License as published by
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the Free Software Foundation, either version 3 of the License, or
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(at your option) any later version.
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OpenFOAM is distributed in the hope that it will be useful, but WITHOUT
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ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or
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FITNESS FOR A PARTICULAR PURPOSE. See the GNU General Public License
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for more details.
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You should have received a copy of the GNU General Public License
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along with OpenFOAM. If not, see <http://www.gnu.org/licenses/>.
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Application
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Q
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Description
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Calculates and writes the second invariant of the velocity gradient tensor.
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Q = 0.5*(sqr(tr(gradU)) - tr(((gradU)&(gradU)))) [1/s^2]
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The -noWrite option just outputs the max/min values without writing
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the field.
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\*---------------------------------------------------------------------------*/
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#include "calc.H"
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#include "fvc.H"
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// * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * //
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void Foam::calc(const argList& args, const Time& runTime, const fvMesh& mesh)
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{
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bool writeResults = !args.optionFound("noWrite");
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IOobject Uheader
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(
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"U",
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runTime.timeName(),
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mesh,
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IOobject::MUST_READ
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);
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if (Uheader.headerOk())
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{
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Info<< " Reading U" << endl;
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volVectorField U(Uheader, mesh);
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volTensorField gradU(fvc::grad(U));
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volScalarField Q
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(
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IOobject
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(
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"Q",
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runTime.timeName(),
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mesh,
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IOobject::NO_READ,
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IOobject::NO_WRITE
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),
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0.5*(sqr(tr(gradU)) - tr(((gradU)&(gradU))))
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);
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/*
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// This is a second way of calculating Q, that delivers results
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// very close, but not identical to the first approach.
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volSymmTensorField S(symm(gradU)); // symmetric part of tensor
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volTensorField W(skew(gradU)); // anti-symmetric part
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volScalarField SS(S && S);
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volScalarField WW(W && W);
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volScalarField Q
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(
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IOobject
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(
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"Q",
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runTime.timeName(),
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mesh,
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IOobject::NO_READ,
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IOobject::NO_WRITE
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),
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0.5*(WW - SS)
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);
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*/
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Info<< "mag(Q) max/min : "
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<< max(Q).value() << " "
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<< min(Q).value() << endl;
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if (writeResults)
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{
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Q.write();
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}
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}
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else
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{
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Info<< " No U" << endl;
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}
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Info<< "\nEnd\n" << endl;
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}
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// ************************************************************************* //
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