85 lines
2.5 KiB
C
85 lines
2.5 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 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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Global
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setDeltaT
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Description
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Reset the timestep to maintain a constant maximum courant Number.
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Reduction of time-step is immediate, but increase is damped to avoid
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unstable oscillations.
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\*---------------------------------------------------------------------------*/
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if (pulseTimeStep)
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{
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const scalar t = runTime.timeOutputValue();
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const scalar T = pulsePeriod;
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const scalar neg_saw_t = (t - floor(t/T+1.)*T);
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const bool inPulse = neg_saw_t >= -pulseTime;
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if (inPulse)
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{
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runTime.setDeltaT (deltaTpulse);
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Info<< "deltaT to proceed the pulse time " << endl;
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}
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else
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{
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const scalar eta = - pulseTime - neg_saw_t;
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if (eta >= deltaTidle)
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{
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runTime.setDeltaT (deltaTidle);
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Info<< "deltaT to proceed the idle time " << endl;
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}
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else
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{
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runTime.setDeltaT (deltaTpulse);
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Info<< "deltaT to the start of the pulse " << endl;
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}
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}
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Info<< "deltaT = " << runTime.deltaTValue() << endl;
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}
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else if (adjustTimeStep)
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{
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CoNum = max(CoNum, CoNumVe);
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scalar maxDeltaTFact = maxCo/(CoNum + SMALL);
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scalar deltaTFact = min(min(maxDeltaTFact, 1.0 + 0.1*maxDeltaTFact), 1.2);
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runTime.setDeltaT
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(
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min
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(
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deltaTFact*runTime.deltaTValue(),
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maxDeltaT
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)
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);
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Info<< "deltaT = " << runTime.deltaTValue() << endl;
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}
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// ************************************************************************* //
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