split forces into coupled and non-coupled

src/lagrangian/intermediate/particleForces/particleForces.C

@@ -115,7 +115,7 @@ const Foam::word& Foam::particleForces::gradUName() const
 }
 
 
-Foam::vector Foam::particleForces::calc
+Foam::vector Foam::particleForces::calcCoupled
 (
     const label cellI,
     const scalar dt,
@@ -127,12 +127,6 @@ Foam::vector Foam::particleForces::calc
 {
     vector Ftot = vector::zero;
 
-    // Gravity force
-    if (gravity_)
-    {
-        Ftot += g_*(1.0 - rhoc/rho);
-    }
-
     // Virtual mass force
     if (virtualMass_)
     {
@@ -152,5 +146,27 @@ Foam::vector Foam::particleForces::calc
 }
 
 
+Foam::vector Foam::particleForces::calcNonCoupled
+(
+    const label cellI,
+    const scalar dt,
+    const scalar rhoc,
+    const scalar rho,
+    const vector& Uc,
+    const vector& U
+) const
+{
+    vector Ftot = vector::zero;
+
+    // Gravity force
+    if (gravity_)
+    {
+        Ftot += g_*(1.0 - rhoc/rho);
+    }
+
+    return Ftot;
+}
+
+
 // ************************************************************************* //
 

src/lagrangian/intermediate/particleForces/particleForces.H

@@ -132,8 +132,19 @@ public:
 
        // Evaluation
 
-            //- Calculate the net particle force
-            vector calc
+            //- Calculate action/reaction forces between carrier and particles
+            vector calcCoupled
+            (
+                const label cellI,
+                const scalar dt,
+                const scalar rhoc,
+                const scalar rho,
+                const vector& Uc,
+                const vector& U
+            ) const;
+
+            //- Calculate external forces applied to the particles
+            vector calcNonCoupled
             (
                 const label cellI,
                 const scalar dt,