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setDeltaT.H

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00001 /*---------------------------------------------------------------------------*\
00002   =========                 |
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00024 
00025 Global
00026     setDeltaT
00027 
00028 Description
00029     Reset the timestep to maintain a constant maximum courant Number.
00030     Reduction of time-step is imediate but increase is damped to avoid
00031     unstable oscillations.
00032 
00033 \*---------------------------------------------------------------------------*/
00034 
00035 if (adjustTimeStep)
00036 {
00037     scalar maxDeltaTFact = maxCo/(CoNum + SMALL);
00038     scalar deltaTFact = min(min(maxDeltaTFact, 1.0 + 0.1*maxDeltaTFact), 1.2);
00039 
00040     runTime.setDeltaT
00041     (
00042         min
00043         (
00044             deltaTFact*runTime.deltaT().value(),
00045             maxDeltaT
00046         )
00047     );
00048     
00049     Info<< "deltaT = " <<  runTime.deltaT().value() << endl;
00050 }
00051 
00052 // ************************************************************************* //
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