diff --git a/src/lagrangian/intermediate/submodels/ForceTypes/ParticleForceList/ParticleForceList.C b/src/lagrangian/intermediate/submodels/ForceTypes/ParticleForceList/ParticleForceList.C
index c4ad6aa5d7..04016823b4 100644
--- a/src/lagrangian/intermediate/submodels/ForceTypes/ParticleForceList/ParticleForceList.C
+++ b/src/lagrangian/intermediate/submodels/ForceTypes/ParticleForceList/ParticleForceList.C
@@ -2,7 +2,7 @@
   =========                 |
   \\      /  F ield         | OpenFOAM: The Open Source CFD Toolbox
    \\    /   O peration     |
-    \\  /    A nd           | Copyright (C) 2011 OpenFOAM Foundation
+    \\  /    A nd           | Copyright (C) 2011-2012 OpenFOAM Foundation
      \\/     M anipulation  |
 -------------------------------------------------------------------------------
 License
@@ -180,4 +180,21 @@ Foam::forceSuSp Foam::ParticleForceList<CloudType>::calcNonCoupled
 }
 
 
+template<class CloudType>
+Foam::scalar Foam::ParticleForceList<CloudType>::massEff
+(
+    const typename CloudType::parcelType& p,
+    const scalar mass
+) const
+{
+    scalar massEff = mass;
+    forAll(*this, i)
+    {
+        massEff += this->operator[](i).massAdd(p, mass);
+    }
+
+    return massEff;
+}
+
+
 // ************************************************************************* //
diff --git a/src/lagrangian/intermediate/submodels/ForceTypes/ParticleForceList/ParticleForceList.H b/src/lagrangian/intermediate/submodels/ForceTypes/ParticleForceList/ParticleForceList.H
index 5eda11a0f5..fe5f561268 100644
--- a/src/lagrangian/intermediate/submodels/ForceTypes/ParticleForceList/ParticleForceList.H
+++ b/src/lagrangian/intermediate/submodels/ForceTypes/ParticleForceList/ParticleForceList.H
@@ -130,6 +130,13 @@ public:
                 const scalar Re,
                 const scalar muc
             ) const;
+
+            //- Return the effective mass
+            virtual scalar massEff
+            (
+                const typename CloudType::parcelType& p,
+                const scalar mass
+            ) const;
 };
 
 
diff --git a/src/lagrangian/intermediate/submodels/Kinematic/ParticleForces/ParticleForce/ParticleForce.C b/src/lagrangian/intermediate/submodels/Kinematic/ParticleForces/ParticleForce/ParticleForce.C
index fc4ba1314b..7adbb47ebd 100644
--- a/src/lagrangian/intermediate/submodels/Kinematic/ParticleForces/ParticleForce/ParticleForce.C
+++ b/src/lagrangian/intermediate/submodels/Kinematic/ParticleForces/ParticleForce/ParticleForce.C
@@ -2,7 +2,7 @@
   =========                 |
   \\      /  F ield         | OpenFOAM: The Open Source CFD Toolbox
    \\    /   O peration     |
-    \\  /    A nd           | Copyright (C) 2011 OpenFOAM Foundation
+    \\  /    A nd           | Copyright (C) 2011-2012 OpenFOAM Foundation
      \\/     M anipulation  |
 -------------------------------------------------------------------------------
 License
@@ -27,7 +27,6 @@ License
 
 // * * * * * * * * * * * * * * * * Constructors  * * * * * * * * * * * * * * //
 
-
 template<class CloudType>
 Foam::ParticleForce<CloudType>::ParticleForce
 (
@@ -120,6 +119,17 @@ Foam::forceSuSp Foam::ParticleForce<CloudType>::calcNonCoupled
 }
 
 
+template<class CloudType>
+Foam::scalar Foam::ParticleForce<CloudType>::massAdd
+(
+    const typename CloudType::parcelType& p,
+    const scalar mass
+) const
+{
+    return 0.0;
+}
+
+
 // * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * //
 
 #include "ParticleForceNew.C"
diff --git a/src/lagrangian/intermediate/submodels/Kinematic/ParticleForces/ParticleForce/ParticleForce.H b/src/lagrangian/intermediate/submodels/Kinematic/ParticleForces/ParticleForce/ParticleForce.H
index c5a6cf01d7..a72abc3217 100644
--- a/src/lagrangian/intermediate/submodels/Kinematic/ParticleForces/ParticleForce/ParticleForce.H
+++ b/src/lagrangian/intermediate/submodels/Kinematic/ParticleForces/ParticleForce/ParticleForce.H
@@ -2,7 +2,7 @@
   =========                 |
   \\      /  F ield         | OpenFOAM: The Open Source CFD Toolbox
    \\    /   O peration     |
-    \\  /    A nd           | Copyright (C) 2011 OpenFOAM Foundation
+    \\  /    A nd           | Copyright (C) 2011-2012 OpenFOAM Foundation
      \\/     M anipulation  |
 -------------------------------------------------------------------------------
 License
@@ -47,7 +47,7 @@ namespace Foam
 {
 
 /*---------------------------------------------------------------------------*\
-                      Class ParticleForce Declaration
+                        Class ParticleForce Declaration
 \*---------------------------------------------------------------------------*/
 
 template<class CloudType>
@@ -169,6 +169,13 @@ public:
                 const scalar Re,
                 const scalar muc
             ) const;
+
+            //- Return the added mass
+            virtual scalar massAdd
+            (
+                const typename CloudType::parcelType& p,
+                const scalar mass
+            ) const;
 };