setDeltaT.H
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25 
26 Global
27  setDeltaT
28 
29 Description
30  Reset the timestep to maintain a constant maximum courant Number.
31  Reduction of time-step is immediate, but increase is damped to avoid
32  unstable oscillations.
33 
34 \*---------------------------------------------------------------------------*/
35 
36 if (adjustTimeStep)
37 {
38  scalar maxDeltaTFact = maxCo/(CoNum + SMALL);
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 // ************************************************************************* //
runTime
engineTime & runTime
Definition: createEngineTime.H:13
maxDeltaT
maxDeltaT
Definition: readEngineTimeControls.H:3
Foam::endl
Ostream & endl(Ostream &os)
Add newline and flush stream.
Definition: Ostream.H:350
Foam::min
label min(const labelHashSet &set, label minValue=labelMax)
Find the min value in labelHashSet, optionally limited by second argument.
Definition: hashSets.C:33
Foam::Info
messageStream Info
Information stream (uses stdout - output is on the master only)
adjustTimeStep
bool adjustTimeStep
Definition: createTimeControls.H:32
CoNum
scalar CoNum
Definition: compressibleCourantNo.H:31
maxCo
scalar maxCo
Definition: createTimeControls.H:35