pass label by value instead of reference

index does not get modified; also avoid potential problems in case int
needs to be cast to a label of different size;

src/lagrangian/cfdemParticle/subModels/forceModel/forceSubModels/ScaleForce/ScaleForce.C

@@ -62,7 +62,7 @@ ScaleForce::~ScaleForce()
 // * * * * * * * * * * * * * * * Member Functions  * * * * * * * * * * * * * //
 void ScaleForce::partToArray
 (
-    label& index,
+    label index,
     vector& dragTot,
     const vector& dragEx,
     const vector& Ufluid,

src/lagrangian/cfdemParticle/subModels/forceModel/forceSubModels/ScaleForce/ScaleForce.H

@@ -70,8 +70,8 @@ public:
 
 
     // Member Functions
-	
-	void partToArray(label&, vector&, const vector&, const vector& Ufluid=vector::zero, scalar Cd=scalar(0)) const;
+
+        void partToArray(label, vector&, const vector&, const vector& Ufluid=vector::zero, scalar Cd=scalar(0)) const;
 
         word myType() const{return typeName; };
 };

src/lagrangian/cfdemParticle/subModels/forceModel/forceSubModels/forceSubModel/forceSubModel.C

@@ -131,7 +131,7 @@ forceSubModel::~forceSubModel()
 // * * * * * * * * * * * * * * * * Member Fct  * * * * * * * * * * * * * * * //
 void forceSubModel::partToArray
 (
-    label& index,
+    label index,
     vector& dragTot,
     const vector& dragEx,
     const vector& Ufluid,

src/lagrangian/cfdemParticle/subModels/forceModel/forceSubModels/forceSubModel/forceSubModel.H

@@ -130,7 +130,7 @@ public:
 
 
     // Member Functions
-        virtual void partToArray(label&, vector&, const vector&, const vector& Ufluid=vector::zero, scalar Cd=scalar(0)) const;
+        virtual void partToArray(label, vector&, const vector&, const vector& Ufluid=vector::zero, scalar Cd=scalar(0)) const;
 
         virtual void explicitCorr(vector&, vector&, scalar&, vector&, const vector&, vector&, const vector&, bool,label index=100) const;
 

src/lagrangian/cfdemParticle/subModels/forceModel/forceSubModels/scaleForceBoundary/scaleForceBoundary.C

@@ -97,7 +97,7 @@ scaleForceBoundary::~scaleForceBoundary()
 // * * * * * * * * * * * * * * * Member Functions  * * * * * * * * * * * * * //
 void scaleForceBoundary::partToArray
 (
-    label& index,
+    label index,
     vector& dragTot,
     const vector& dragEx,
     const vector& Ufluid,

src/lagrangian/cfdemParticle/subModels/forceModel/forceSubModels/scaleForceBoundary/scaleForceBoundary.H

@@ -82,10 +82,10 @@ public:
 
 
     // Member Functions
-	
-	void partToArray(label&, vector&, const vector&, const vector& Ufluid=vector::zero, scalar Cd=scalar(0)) const;
 
-        word myType() const{return typeName; };
+        void partToArray(label, vector&, const vector&, const vector& Ufluid=vector::zero, scalar Cd=scalar(0)) const;
+
+        word myType() const {return typeName; }
 };