WIP: ENH: renovate v2-f turbulence closure model

• Implementation-related:

  • corrects strain rate and tke production term to enable consistent compressible formulation

  • corrects Ts and Ls function expressions according to the original paper

  • corrects the transport equation terms to enable consistent compressible formulation

  • adds protections against floating-point exceptions

  • Usage-related:

    • updates the header documentation
    • allows the hard-coded constants to be tuned by users
    • adds tags to easily track the implementations' expressions in the original papers

src/TurbulenceModels/turbulenceModels/RAS/v2f/v2f.C

@@ -46,7 +46,7 @@ tmp<volScalarField> v2f<BasicTurbulenceModel>::Ts
 {
     // SAF: limiting thermo->nu(). If psiThermo is used rho might be < 0
     // temporarily when p < 0 then nu < 0 which needs limiting
-    // (BL-Eq. 8 & Table 5)
+    // (BL:Eq. 8 & Table 5)
     return
         max
         (
@@ -75,7 +75,7 @@ tmp<volScalarField> v2f<BasicTurbulenceModel>::Ls
 {
     // SAF: limiting thermo->nu(). If psiThermo is used rho might be < 0
     // temporarily when p < 0 then nu < 0 which needs limiting
-    // (BL-Eq. 8 & Table 5)
+    // (BL:Eq. 8 & Table 5)
     return
         CL_*max
         (
@@ -102,7 +102,7 @@ tmp<volScalarField> v2f<BasicTurbulenceModel>::Ls
 template<class BasicTurbulenceModel>
 void v2f<BasicTurbulenceModel>::correctNut()
 {
-    // (D-Eq. 7)
+    // (D:Eq. 7)
     this->nut_ =
         min
         (
@@ -431,35 +431,35 @@ void v2f<BasicTurbulenceModel>::correct()
         )
     );
 
-    // (LK-p. 54; D-Eq. 2)
+    // (LK:p. 54; D:Eq. 2)
     tmp<volTensorField> tgradU(fvc::grad(U));
 
     const volSymmTensorField S("Sij", symm(tgradU()));
 
     const volScalarField G(this->GName(), nut*(2.0*(dev(S) && tgradU)));
 
-    // (LK-Eqs. 4-5)
+    // (LK:Eqs. 4-5)
     volScalarField C
     (
         "C",
         (sqrt(6.0)*Cmu_)*(sqrt(S && S)*v2_) + this->epsilonMin_
     );
 
-    // (LK-Eq. 4)
+    // (LK:Eq. 4)
     T_ = this->Ts(C);
     bound(T_, TMin_);
 
-    // (LK-Eq. 5)
+    // (LK:Eq. 5)
     const volScalarField L2(type() + ":L2", sqr(Ls(C)) + L2Min_);
 
-    // (LK-Eq. 15; D-Eq. 6)
+    // (LK:Eq. 15; D:Eq. 6)
     const volScalarField::Internal v2fAlpha
     (
         type() + ":alpha",
         1.0/T_()*((C1_ - 6.0)*v2_() - 2.0/3.0*k_()*(C1_ - 1.0))
     );
 
-    // (LK-Eq. 17)
+    // (LK:Eq. 17)
     const volScalarField::Internal Ceps1
     (
         "Ceps1",
@@ -470,7 +470,7 @@ void v2f<BasicTurbulenceModel>::correct()
     // Update epsilon (and possibly G) at the wall
     epsilon_.boundaryFieldRef().updateCoeffs();
 
-    // Turbulent kinetic energy dissipation rate equation (LK-Eq. 7)
+    // Turbulent kinetic energy dissipation rate equation (LK:Eq. 7)
     // k/T ~ epsilon
     tmp<fvScalarMatrix> epsEqn
     (
@@ -496,8 +496,8 @@ void v2f<BasicTurbulenceModel>::correct()
     bound(epsilon_, this->epsilonMin_);
 
 
-    // Turbulent kinetic energy equation (LK-Eq. 6)
-    // epsilon/k ~ 1/Ts (LK-p. 55)
+    // Turbulent kinetic energy equation (LK:Eq. 6)
+    // epsilon/k ~ 1/Ts (LK:p. 55)
     tmp<fvScalarMatrix> kEqn
     (
         fvm::ddt(alpha, rho, k_)
@@ -517,7 +517,7 @@ void v2f<BasicTurbulenceModel>::correct()
     bound(k_, this->kMin_);
 
 
-    // Elliptic relaxation function equation (LK-Eq. 15)
+    // Elliptic relaxation function equation (LK:Eq. 15)
     tmp<fvScalarMatrix> fEqn
     (
       - fvm::laplacian(f_)
@@ -534,7 +534,7 @@ void v2f<BasicTurbulenceModel>::correct()
     bound(f_, fMin_);
 
 
-    // Wall-normal fluctuating velocity scale equation (LK-Eq. 14; D-Eq. 6)
+    // Wall-normal fluctuating velocity scale equation (LK:Eq. 14; D:Eq. 6)
     tmp<fvScalarMatrix> v2Eqn
     (
         fvm::ddt(alpha, rho, v2_)
@@ -553,7 +553,7 @@ void v2f<BasicTurbulenceModel>::correct()
     bound(v2_, v2Min_);
 
     // Update the turbulent time scale
-    C = (sqrt(6.0)*Cmu_)*(sqrt(S && S)*v2_);
+    C = (sqrt(6.0)*Cmu_)*(sqrt(S && S)*v2_) + this->epsilonMin_;
     T_ = this->Ts(C);
 
     correctNut();