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 maxDeltaTFact =
37  min(maxCo/(CoNum + small), maxAlphaCo/(alphaCoNum + small));
38 
39  scalar deltaTFact = min(min(maxDeltaTFact, 1.0 + 0.1*maxDeltaTFact), 1.2);
40 
41  runTime.setDeltaT
42  (
43  min
44  (
45  deltaTFact*runTime.deltaTValue(),
46  maxDeltaT
47  )
48  );
49 
50  Info<< "deltaT = " << runTime.deltaTValue() << endl;
51 }
52 
53 // ************************************************************************* //
engineTime & runTime
Ostream & endl(Ostream &os)
Add newline and flush stream.
Definition: Ostream.H:251
scalar CoNum
scalar maxCo
dimensioned< Type > min(const dimensioned< Type > &, const dimensioned< Type > &)
scalar maxAlphaCo(runTime.controlDict().lookup< scalar >("maxAlphaCo"))
messageStream Info
scalar alphaCoNum
bool adjustTimeStep