setMultiRegionDeltaT.H
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25 
26 Global
27  setMultiRegionDeltaT
28 
29 Description
30  Reset the timestep to maintain a constant maximum courant and
31  diffusion Numbers. Reduction of time-step is immediate, but
32  increase is damped to avoid unstable oscillations.
33 
34 \*---------------------------------------------------------------------------*/
35 
36 if (adjustTimeStep)
37 {
38  if (CoNum == -GREAT)
39  {
40  CoNum = SMALL;
41  }
42 
43  if (DiNum == -GREAT)
44  {
45  DiNum = SMALL;
46  }
47 
48  scalar maxDeltaTFluid = maxCo/(CoNum + SMALL);
49  scalar maxDeltaTSolid = maxDi/(DiNum + SMALL);
50 
51  scalar deltaTFluid =
52  min
53  (
54  min(maxDeltaTFluid, 1.0 + 0.1*maxDeltaTFluid),
55  1.2
56  );
57 
58  runTime.setDeltaT
59  (
60  min
61  (
62  min(deltaTFluid, maxDeltaTSolid)*runTime.deltaT().value(),
63  maxDeltaT
64  )
65  );
66 
67  Info<< "deltaT = " << runTime.deltaT().value() << endl;
68 }
69 
70 // ************************************************************************* //
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:369
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 (stdout output on master, null elsewhere)
DiNum
scalar DiNum
Definition: solidRegionDiffusionNo.H:1
adjustTimeStep
bool adjustTimeStep
Definition: createTimeControls.H:32
maxDi
scalar maxDi
Definition: createRegionControls.H:23
CoNum
scalar CoNum
Definition: compressibleCourantNo.H:31
maxCo
scalar maxCo
Definition: createTimeControls.H:35