FreeFOAM The Cross-Platform CFD Toolkit
kEpsilon.H
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2 {
3  if (mesh.changing())
4  {
5  y.correct();
6  }
7 
8  tmp<volTensorField> tgradUb = fvc::grad(Ub);
9  volScalarField G = 2*nutb*(tgradUb() && dev(symm(tgradUb())));
10  tgradUb.clear();
11 
13 
14  // Dissipation equation
15  fvScalarMatrix epsEqn
16  (
17  fvm::ddt(beta, epsilon)
18  + fvm::div(phib, epsilon)
20  (
21  alphaEps*nuEffb, epsilon,
22  "laplacian(DepsilonEff,epsilon)"
23  )
24  ==
25  C1*beta*G*epsilon/k
26  - fvm::Sp(C2*beta*epsilon/k, epsilon)
27  );
28 
30 
31  epsEqn.relax();
32  epsEqn.solve();
33 
34  epsilon.max(dimensionedScalar("zero", epsilon.dimensions(), 1.0e-15));
35 
36 
37  // Turbulent kinetic energy equation
38  fvScalarMatrix kEqn
39  (
40  fvm::ddt(beta, k)
41  + fvm::div(phib, k)
43  (
44  alphak*nuEffb, k,
45  "laplacian(DkEff,k)"
46  )
47  ==
48  beta*G
49  - fvm::Sp(beta*epsilon/k, k)
50  );
51  kEqn.relax();
52  kEqn.solve();
53 
54  k.max(dimensionedScalar("zero", k.dimensions(), 1.0e-8));
55 
56  //- Re-calculate turbulence viscosity
57  nutb = Cmu*sqr(k)/epsilon;
58 
60 }
61 
62 nuEffb = nutb + nub;