FreeFOAM The Cross-Platform CFD Toolkit
DeardorffDiffStress.H
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23 
24 Class
25  Foam::compressible::LESModels::DeardorffDiffStress
26 
27 Description
28  Differential SGS Stress Equation Model for compressible flows
29 
30  The DSEM uses a model version of the full balance equation for the SGS
31  stress tensor to simulate the behaviour of B.
32  Thus,
33  @verbatim
34  d/dt(rho*B) + div(rho*U*B) - div(muSgs*grad(B))
35  =
36  P - c1*rho*epsilon/k*B - 0.667*(1 - c1)*rho*epsilon*I - c2*(P - 0.333*trP*I)
37 
38  where
39 
40  k = 0.5*trB,
41  epsilon = ce*k^3/2/delta,
42  epsilon/k = ce*k^1/2/delta
43  P = -rho*(B'L + L'B)
44  muSgs = ck*rho*sqrt(k)*delta
45  muEff = muSgs + mu
46  @endverbatim
47 
48 SourceFiles
49  DeardorffDiffStress.C
50 
51 \*---------------------------------------------------------------------------*/
52 
53 #ifndef compressibleDeardorffDiffStress_H
54 #define compressibleDeardorffDiffStress_H
55 
57 
58 // * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * //
59 
60 namespace Foam
61 {
62 namespace compressible
63 {
64 namespace LESModels
65 {
66 
67 /*---------------------------------------------------------------------------*\
68  Class DeardorffDiffStress Declaration
69 \*---------------------------------------------------------------------------*/
70 
72 :
73  public GenSGSStress
74 {
75  // Private data
76 
79 
80 
81  // Private Member Functions
82 
83  //- Update sub-grid scale fields
84  void updateSubGridScaleFields(const volScalarField& K);
85 
86  // Disallow default bitwise copy construct and assignment
88  DeardorffDiffStress& operator=(const DeardorffDiffStress&);
89 
90 
91 public:
92 
93  //- Runtime type information
94  TypeName("DeardorffDiffStress");
95 
96  // Constructors
97 
98  //- Constructor from components
100  (
101  const volScalarField& rho,
102  const volVectorField& U,
103  const surfaceScalarField& phi,
104  const basicThermo& thermoPhysicalModel
105  );
106 
107 
108  //- Destructor
110  {}
111 
112 
113  // Member Functions
114 
115  //- Return the effective diffusivity for B
117  {
118  return tmp<volScalarField>
119  (
120  new volScalarField("DBEff", muSgs_ + mu())
121  );
122  }
123 
124  //- Correct Eddy-Viscosity and related properties
125  virtual void correct(const tmp<volTensorField>& gradU);
126 
127  //- Read LESProperties dictionary
128  virtual bool read();
129 };
130 
131 
132 // * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * //
133 
134 } // End namespace LESModels
135 } // End namespace compressible
136 } // End namespace Foam
137 
138 // * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * //
139 
140 #endif
141 
142 // ************************ vim: set sw=4 sts=4 et: ************************ //