00001 /*---------------------------------------------------------------------------*\ 00002 ========= | 00003 \\ / F ield | OpenFOAM: The Open Source CFD Toolbox 00004 \\ / O peration | 00005 \\ / A nd | Copyright (C) 1991-2010 OpenCFD Ltd. 00006 \\/ M anipulation | 00007 ------------------------------------------------------------------------------- 00008 License 00009 This file is part of OpenFOAM. 00010 00011 OpenFOAM is free software: you can redistribute it and/or modify it 00012 under the terms of the GNU General Public License as published by 00013 the Free Software Foundation, either version 3 of the License, or 00014 (at your option) any later version. 00015 00016 OpenFOAM is distributed in the hope that it will be useful, but WITHOUT 00017 ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or 00018 FITNESS FOR A PARTICULAR PURPOSE. See the GNU General Public License 00019 for more details. 00020 00021 You should have received a copy of the GNU General Public License 00022 along with OpenFOAM. If not, see <http://www.gnu.org/licenses/>. 00023 00024 Global 00025 setDeltaT 00026 00027 Description 00028 Reset the timestep to maintain a constant maximum courant Number. 00029 Reduction of time-step is imediate but increase is damped to avoid 00030 unstable oscillations. 00031 00032 \*---------------------------------------------------------------------------*/ 00033 00034 if (adjustTimeStep) 00035 { 00036 scalar maxDeltaTFact = 00037 min(maxCo/(CoNum + SMALL), maxAcousticCo/(acousticCoNum + SMALL)); 00038 00039 scalar deltaTFact = min(min(maxDeltaTFact, 1.0 + 0.1*maxDeltaTFact), 1.2); 00040 00041 runTime.setDeltaT 00042 ( 00043 min 00044 ( 00045 deltaTFact*runTime.deltaT().value(), 00046 maxDeltaT 00047 ) 00048 ); 00049 00050 Info<< "deltaT = " << runTime.deltaT().value() << endl; 00051 } 00052 00053 // ************************ vim: set sw=4 sts=4 et: ************************ //
