Stochastic.H
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23 
24 Class
25  Foam::IsotropyModels::Stochastic
26 
27 Description
28  Stochastic return-to-isotropy model.
29 
30  Particle velocities are modified by sampling a gaussian-plus-delta
31  distribution, which depends on a time-scale. This randomises some particle
32  velocities whilst leaving others unchanged. The lower the value of the
33  time-scale, the greater the proportion of particle velocities affected.
34 
35  A correction step is performed at the end to ensure that the model
36  conserves both momentum and granular temperature.
37 
38  Reference:
39  \verbatim
40  "Inclusion of collisional return-to-isotropy in the MP-PIC method"
41  P O'Rourke and D Snider
42  Chemical Engineering Science
43  Volume 80, Issue 0, Pages 39-54, December 2012
44  \endverbatim
45 
46 SourceFiles
47  Stochastic.C
48 
49 \*---------------------------------------------------------------------------*/
50 
51 #ifndef Stochastic_H
52 #define Stochastic_H
53 
54 #include "IsotropyModel.H"
55 
56 // * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * //
57 
58 namespace Foam
59 {
60 namespace IsotropyModels
61 {
62 
63 /*---------------------------------------------------------------------------*\
64  Class Stochastic Declaration
65 \*---------------------------------------------------------------------------*/
66 
67 template<class CloudType>
68 class Stochastic
69 :
70  public IsotropyModel<CloudType>
71 {
72  // Private Member Functions
73 
74  //- Sample a gaussian distribution using the Box-Muller method
75  scalar sampleGauss();
76 
77 
78 public:
79 
80  //- Runtime type information
81  TypeName("stochastic");
82 
83  // Constructors
84 
85  //- Construct from components
87 
88  //- Construct copy
90 
91  //- Construct and return a clone
93  {
95  (
96  new Stochastic<CloudType>(*this)
97  );
98  }
99 
100 
101  //- Destructor
102  virtual ~Stochastic();
103 
104 
105  //- Member Functions
106 
107  //- Calculate velocities
108  virtual void calculate();
109 };
110 
111 
112 // * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * //
113 
114 } // End namespace IsotropyModels
115 } // End namespace Foam
116 
117 // * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * //
118 
119 #ifdef NoRepository
120  #include "Stochastic.C"
121 #endif
122 
123 // * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * //
124 
125 #endif
126 
127 // ************************************************************************* //
A list of keyword definitions, which are a keyword followed by any number of values (e...
Definition: dictionary.H:156
Stochastic return-to-isotropy model.
Definition: Stochastic.H:67
const dictionary & dict() const
Return const access to the cloud dictionary.
Definition: subModelBase.C:110
const CloudType & owner() const
Return const access to the owner cloud.
virtual autoPtr< IsotropyModel< CloudType > > clone() const
Construct and return a clone.
Definition: Stochastic.H:91
Stochastic(const dictionary &dict, CloudType &owner)
Construct from components.
Definition: Stochastic.C:32
Base class for collisional return-to-isotropy models.
Definition: MPPICCloud.H:59
virtual ~Stochastic()
Destructor.
Definition: Stochastic.C:54
virtual void calculate()
Member Functions.
Definition: Stochastic.C:97
An auto-pointer similar to the STL auto_ptr but with automatic casting to a reference to the type and...
Definition: PtrList.H:52
Templated base class for dsmc cloud.
Definition: DSMCCloud.H:75
TypeName("stochastic")
Runtime type information.
Namespace for OpenFOAM.