setMultiRegionDeltaT.H
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23 
24 Global
25  setMultiRegionDeltaT
26 
27 Description
28  Reset the timestep to maintain a constant maximum courant and
29  diffusion Numbers. Reduction of time-step is immediate, but
30  increase is damped to avoid unstable oscillations.
31 
32 \*---------------------------------------------------------------------------*/
33 
34 if (adjustTimeStep)
35 {
36  if (CoNum == -GREAT)
37  {
38  CoNum = SMALL;
39  }
40 
41  if (DiNum == -GREAT)
42  {
43  DiNum = SMALL;
44  }
45 
46  scalar maxDeltaTFluid = maxCo/(CoNum + SMALL);
47  scalar maxDeltaTSolid = maxDi/(DiNum + SMALL);
48 
49  scalar deltaTFluid =
50  min
51  (
52  min(maxDeltaTFluid, 1.0 + 0.1*maxDeltaTFluid),
53  1.2
54  );
55 
56  runTime.setDeltaT
57  (
58  min
59  (
60  min(deltaTFluid, maxDeltaTSolid)*runTime.deltaT().value(),
61  maxDeltaT
62  )
63  );
64 
65  Info<< "deltaT = " << runTime.deltaT().value() << endl;
66 }
67 
68 // ************************************************************************* //
scalar DiNum
bool adjustTimeStep
messageStream Info
Ostream & endl(Ostream &os)
Add newline and flush stream.
Definition: Ostream.H:251
scalar maxDeltaT
scalar maxDi
scalar CoNum
dimensioned< Type > min(const dimensioned< Type > &, const dimensioned< Type > &)
scalar maxCo