ENH: Adding momemtum predictor to chtSimpleFoam

applications/solvers/heatTransfer/chtMultiRegionFoam/chtMultiRegionSimpleFoam/fluid/UEqn.H

@@ -16,17 +16,20 @@
 
     fvOptions.constrain(UEqn);
 
-    solve
-    (
-        UEqn
-     ==
-        fvc::reconstruct
+    if (momentumPredictor)
+    {
+        solve
         (
+            UEqn
+        ==
+            fvc::reconstruct
             (
-              - ghf*fvc::snGrad(rho)
-              - fvc::snGrad(p_rgh)
-            )*mesh.magSf()
-        )
-    );
+                (
+                - ghf*fvc::snGrad(rho)
+                - fvc::snGrad(p_rgh)
+                )*mesh.magSf()
+            )
+        );
 
-    fvOptions.correct(U);
+        fvOptions.correct(U);
+    }

applications/solvers/heatTransfer/chtMultiRegionFoam/chtMultiRegionSimpleFoam/fluid/readFluidMultiRegionSIMPLEControls.H

@@ -2,3 +2,6 @@
 
     const int nNonOrthCorr =
         simple.lookupOrDefault<int>("nNonOrthogonalCorrectors", 0);
+
+    const bool momentumPredictor =
+        simple.lookupOrDefault("momentumPredictor", true);