BUG: chemFoam: Calculate the specific gas constant at each time step

- Mantis bug: 315

applications/solvers/combustion/chemFoam/createFields.H

@@ -45,9 +45,29 @@
         ),
         thermo.rho()
     );
+
     volScalarField& p = thermo.p();
     volScalarField& hs = thermo.hs();
 
+    volScalarField Rspecific
+    (
+        IOobject
+        (
+            "Rspecific",
+            runTime.timeName(),
+            runTime,
+            IOobject::NO_READ,
+            IOobject::AUTO_WRITE
+        ),
+        mesh,
+        dimensionedScalar
+        (
+            "zero",
+            dimensionSet(dimEnergy/dimMass/dimTemperature),
+            0.0
+        )
+    );
+
     volVectorField U
     (
         IOobject

applications/solvers/combustion/chemFoam/pEqn.H

@@ -3,7 +3,15 @@
     rho = thermo.rho();
     if (constProp == "volume")
     {
-        p[0] = rho0*R0*thermo.T()[0];
+        scalar invW = 0.0;
+        forAll(Y, i)
+        {
+            invW += Y[i][0]/specieData[i].W();
+        }
+
+        Rspecific[0] = 1000.0*constant::physicoChemical::R.value()*invW;
+
+        p[0] = rho0*Rspecific[0]*thermo.T()[0];
         rho[0] = rho0;
     }
-}
\ No newline at end of file
+}

applications/solvers/combustion/chemFoam/readInitialConditions.H

@@ -106,6 +106,7 @@
     scalar rho0 = rho[0];
     scalar u0 = hs0 - p0/rho0;
     scalar R0 = p0/(rho0*T0);
-
+    Rspecific[0] = R0;
+ 
     scalar integratedHeat = 0.0;