setDeltaT.H
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23 
24 Global
25  setDeltaT
26 
27 Description
28  Reset the timestep to maintain a constant maximum courant Number.
29  Reduction of time-step is immediate, but increase is damped to avoid
30  unstable oscillations.
31 
32 \*---------------------------------------------------------------------------*/
33 
34 if (adjustTimeStep)
35 {
36  scalar deltaT =
37  min(maxCo/(CoNum + small), maxAlphaCo/(alphaCoNum + small))
38  *runTime.deltaTValue();
39  deltaT = min(deltaT, fvModels.maxDeltaT());
40  deltaT = min
41  (
42  min(deltaT, runTime.deltaTValue() + 0.1*deltaT),
43  1.2*runTime.deltaTValue()
44  );
45  runTime.setDeltaT(min(deltaT, maxDeltaT));
46 
47  Info<< "deltaT = " << runTime.deltaTValue() << endl;
48 }
49 
50 // ************************************************************************* //
virtual scalar maxDeltaT() const
Return the maximum time-step for stable operation.
Definition: fvModels.C:240
Ostream & endl(Ostream &os)
Add newline and flush stream.
Definition: Ostream.H:251
scalar maxDeltaT
layerAndWeight min(const layerAndWeight &a, const layerAndWeight &b)
scalar CoNum
scalar maxCo
Foam::fvModels & fvModels
scalar maxAlphaCo(runTime.controlDict().lookup< scalar >("maxAlphaCo"))
messageStream Info
scalar alphaCoNum
bool adjustTimeStep