setRDeltaT.H
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25 
26 {
27  volScalarField& rDeltaT = trDeltaT.ref();
28 
29  const dictionary& pimpleDict = pimple.dict();
30 
31  // Maximum flow Courant number
32  scalar maxCo(pimpleDict.lookup<scalar>("maxCo"));
33 
34  // Maximum time scale
35  scalar maxDeltaT(pimpleDict.lookupOrDefault<scalar>("maxDeltaT", great));
36 
37  // Smoothing parameter (0-1) when smoothing iterations > 0
39  (
40  pimpleDict.lookupOrDefault<scalar>("rDeltaTSmoothingCoeff", 0.1)
41  );
42 
43  // Damping coefficient (1-0)
44  scalar rDeltaTDampingCoeff
45  (
46  pimpleDict.lookupOrDefault<scalar>("rDeltaTDampingCoeff", 0.2)
47  );
48 
49  // Maximum change in cell temperature per iteration
50  // (relative to previous value)
51  scalar alphaTemp(pimpleDict.lookupOrDefault("alphaTemp", 0.05));
52 
53 
54  Info<< "Time scales min/max:" << endl;
55 
56  // Cache old reciprocal time scale field
57  volScalarField rDeltaT0("rDeltaT0", rDeltaT);
58 
59  // Flow time scale
60  {
61  rDeltaT.ref() =
62  (
63  fvc::surfaceSum(mag(phi))()()
64  /((2*maxCo)*mesh.V()*rho())
65  );
66 
67  // Limit the largest time scale
68  rDeltaT.max(1/maxDeltaT);
69 
70  Info<< " Flow = "
71  << gMin(1/rDeltaT.primitiveField()) << ", "
72  << gMax(1/rDeltaT.primitiveField()) << endl;
73  }
74 
75  // Reaction source time scale
76  {
77  volScalarField::Internal rDeltaTT
78  (
79  mag
80  (
81  parcels.hsTrans()/(mesh.V()*runTime.deltaT())
82  + combustion->Qdot()()
83  )
84  /(
85  alphaTemp
86  *rho()
87  *thermo.Cp()()()
88  *T()
89  )
90  );
91 
92  Info<< " Temperature = "
93  << gMin(1/(rDeltaTT.field() + vSmall)) << ", "
94  << gMax(1/(rDeltaTT.field() + vSmall)) << endl;
95 
96  rDeltaT.ref() = max
97  (
98  rDeltaT(),
99  rDeltaTT
100  );
101  }
102 
103  // Update the boundary values of the reciprocal time-step
104  rDeltaT.correctBoundaryConditions();
105 
106  // Spatially smooth the time scale field
107  if (rDeltaTSmoothingCoeff < 1.0)
108  {
110  }
111 
112  // Limit rate of change of time scale
113  // - reduce as much as required
114  // - only increase at a fraction of old time scale
115  if
116  (
117  rDeltaTDampingCoeff < 1.0
118  && runTime.timeIndex() > runTime.startTimeIndex() + 1
119  )
120  {
121  rDeltaT = max
122  (
123  rDeltaT,
124  (scalar(1) - rDeltaTDampingCoeff)*rDeltaT0
125  );
126  }
127 
128  Info<< " Overall = "
129  << gMin(1/rDeltaT.primitiveField())
130  << ", " << gMax(1/rDeltaT.primitiveField()) << endl;
131 }
132 
133 
134 // ************************************************************************* //
pimpleNoLoopControl & pimple
dimensioned< Type > max(const dimensioned< Type > &, const dimensioned< Type > &)
Type gMin(const FieldField< Field, Type > &f)
engineTime & runTime
Ostream & endl(Ostream &os)
Add newline and flush stream.
Definition: Ostream.H:251
scalar rDeltaTDampingCoeff(pimpleDict.lookupOrDefault< scalar >("rDeltaTDampingCoeff", 1.0))
rhoReactionThermo & thermo
Definition: createFields.H:28
void smooth(volScalarField &field, const scalar coeff)
Definition: fvcSmooth.C:35
phi
Definition: pEqn.H:104
GeometricField< scalar, fvPatchField, volMesh > volScalarField
Definition: volFieldsFwd.H:57
dynamicFvMesh & mesh
scalar maxCo(pimpleDict.lookupOrDefault< scalar >("maxCo", 0.9))
scalar rDeltaTSmoothingCoeff(pimpleDict.lookupOrDefault< scalar >("rDeltaTSmoothingCoeff", 0.1))
scalar alphaTemp(pimpleDict.lookupOrDefault("alphaTemp", 0.05))
Type gMax(const FieldField< Field, Type > &f)
const volScalarField & T
volScalarField rDeltaT0("rDeltaT0", rDeltaT)
Info<< "Creating combustion model\"<< endl;autoPtr< CombustionModel< psiReactionThermo > > combustion(CombustionModel< psiReactionThermo >::New(thermo, turbulence()))
scalar maxDeltaT(pimpleDict.lookupOrDefault< scalar >("maxDeltaT", great))
messageStream Info
dimensioned< scalar > mag(const dimensioned< Type > &)
tmp< GeometricField< Type, fvPatchField, volMesh > > surfaceSum(const GeometricField< Type, fvsPatchField, surfaceMesh > &ssf)
tmp< volScalarField > trDeltaT
Definition: createRDeltaT.H:3