Compressible solver pEqn.H: Standardised the treatment of density

In rhoPimpleFoam, rhoSimpleFoam, buoyantPimpleFoam and buoyantSimpleFoam the
density prediction step at the start of pEqn.H is now consistent between these
solvers and the other compressible solvers.  If the density is relaxed in the
corrector it is now also relaxed following the predictor which improves
consistency, stability and convergence.

applications/solvers/compressible/rhoPimpleFoam/pEqn.H

@@ -1,6 +1,8 @@
-if ((!mesh.steady() && !pimple.simpleRho()) || pimple.consistent())
+rho = thermo.rho();
+
+if (!pimple.transonic())
 {
-    rho = thermo.rho();
+    rho.relax();
 }
 
 // Thermodynamic density needs to be updated by psi*d(p) after the

applications/solvers/compressible/rhoSimpleFoam/pEqn.H

@@ -1,8 +1,11 @@
-if (simple.consistent())
+rho = thermo.rho();
+
+if (!simple.transonic())
 {
-    rho = thermo.rho();
+    rho.relax();
 }
 
+
 const volScalarField rAU("rAU", 1.0/UEqn.A());
 const surfaceScalarField rhorAUf("rhorAUf", fvc::interpolate(rho*rAU));
 

applications/solvers/heatTransfer/buoyantPimpleFoam/pEqn.H

@@ -1,6 +1,8 @@
-if (!mesh.steady() && !pimple.simpleRho())
+rho = thermo.rho();
+
+if (!pimple.transonic())
 {
-    rho = thermo.rho();
+    rho.relax();
 }
 
 // Thermodynamic density needs to be updated by psi*d(p) after the

applications/solvers/heatTransfer/buoyantSimpleFoam/pEqn.H

@@ -1,5 +1,10 @@
 rho = thermo.rho();
 
+if (!simple.transonic())
+{
+    rho.relax();
+}
+
 const volScalarField rAU("rAU", 1.0/UEqn.A());
 const surfaceScalarField rhorAUf("rhorAUf", fvc::interpolate(rho*rAU));
 volVectorField HbyA(constrainHbyA(rAU*UEqn.H(), U, p_rgh));

tutorials/compressible/rhoSimpleFoam/angledDuctExplicitFixedCoeff/system/fvSolution

@@ -70,13 +70,13 @@ relaxationFactors
     fields
     {
         p               0.3;
-        rho             0.05;
+        rho             0.01;
     }
     equations
     {
         U               0.7;
+        e               0.7;
         "(k|epsilon)"   0.7;
-        e               0.5;
     }
 }
 

tutorials/heatTransfer/buoyantSimpleFoam/circuitBoardCooling/system/fvSolution

@@ -18,12 +18,11 @@ solvers
 {
     p_rgh
     {
-        solver           GAMG;
-        tolerance        1e-7;
-        relTol           0.01;
-
-        smoother         DICGaussSeidel;
+        solver          GAMG;
+        smoother        DICGaussSeidel;
 
+        tolerance       1e-7;
+        relTol          0.01;
     }
 
     "(U|h|k|epsilon|omega)"

tutorials/heatTransfer/buoyantSimpleFoam/iglooWithFridges/system/fvSchemes

@@ -34,7 +34,7 @@ divSchemes
     div(phi,k)      bounded Gauss upwind;
     div(phi,epsilon) bounded Gauss upwind;
 
-    div(phi,Ekp)    bounded Gauss linear;
+    div(phi,Ekp)    Gauss linear;
     div(((rho*nuEff)*dev2(T(grad(U))))) Gauss linear;
 }
 

tutorials/heatTransfer/buoyantSimpleFoam/iglooWithFridges/system/fvSolution

@@ -18,8 +18,9 @@ solvers
 {
     p_rgh
     {
-        solver          PCG;
-        preconditioner  DIC;
+        solver          GAMG;
+        smoother        DICGaussSeidel;
+
         tolerance       1e-8;
         relTol          0.01;
     }