setDeltaT.H

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    This file is part of OpenFOAM.
 
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Global
    setDeltaT
 
Description
    Reset the timestep to maintain a constant maximum courant Number.
    Reduction of time-step is immediate but increase is damped to avoid
    unstable oscillations.
 
\*---------------------------------------------------------------------------*/
 
if (adjustTimeStep)
{
    scalar maxDeltaTFact =
        min(maxCo/(CoNum + SMALL), maxAcousticCo/(acousticCoNum + SMALL));
 
    scalar deltaTFact = min(min(maxDeltaTFact, 1.0 + 0.1*maxDeltaTFact), 1.2);
 
    runTime.setDeltaT
    (
        min
        (
            deltaTFact*runTime.deltaTValue(),
            maxDeltaT
        )
    );
 
    Info<< "deltaT = " <<  runTime.deltaTValue() << endl;
}
 
// ************************************************************************* //