diff --git a/src/finiteVolume/cfdTools/general/fvModels/fvModel.H b/src/finiteVolume/cfdTools/general/fvModels/fvModel.H
index faaeff8c6e..bd03cddd42 100644
--- a/src/finiteVolume/cfdTools/general/fvModels/fvModel.H
+++ b/src/finiteVolume/cfdTools/general/fvModels/fvModel.H
@@ -36,10 +36,12 @@ SourceFiles
 #define fvModel_H
 
 #include "fvMatricesFwd.H"
-#include "volFieldsFwd.H"
+#include "volFields.H"
 #include "dictionary.H"
 #include "dimensionSet.H"
 #include "fvModelM.H"
+#include "geometricOneField.H"
+#include "MeshObject.H"
 
 // * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * //
 
@@ -325,6 +327,48 @@ public:
                 const word& fieldName
             ) const;
 
+            //- Return source for a phase equation
+            template<class Type>
+            tmp<fvMatrix<Type>> source
+            (
+                const volScalarField& alpha,
+                const geometricOneField& rho,
+                const GeometricField<Type, fvPatchField, volMesh>& field
+            ) const;
+
+            //- Return source for a phase equation
+            template<class Type>
+            tmp<fvMatrix<Type>> source
+            (
+                const geometricOneField& alpha,
+                const volScalarField& rho,
+                const GeometricField<Type, fvPatchField, volMesh>& field
+            ) const;
+
+            //- Return source for a phase equation
+            template<class Type>
+            tmp<fvMatrix<Type>> source
+            (
+                const geometricOneField& alpha,
+                const geometricOneField& rho,
+                const GeometricField<Type, fvPatchField, volMesh>& field
+            ) const;
+
+            //- Return source for an equation with a second time derivative
+            template<class Type>
+            tmp<fvMatrix<Type>> d2dt2
+            (
+                const GeometricField<Type, fvPatchField, volMesh>& field
+            ) const;
+
+            //- Return source for an equation with a second time derivative
+            template<class Type>
+            tmp<fvMatrix<Type>> d2dt2
+            (
+                const GeometricField<Type, fvPatchField, volMesh>& field,
+                const word& fieldName
+            ) const;
+
 
         // Mesh changes
 
diff --git a/src/finiteVolume/cfdTools/general/fvModels/fvModelTemplates.C b/src/finiteVolume/cfdTools/general/fvModels/fvModelTemplates.C
index 50282a046b..ea2ac65935 100644
--- a/src/finiteVolume/cfdTools/general/fvModels/fvModelTemplates.C
+++ b/src/finiteVolume/cfdTools/general/fvModels/fvModelTemplates.C
@@ -2,7 +2,7 @@
   =========                 |
   \\      /  F ield         | OpenFOAM: The Open Source CFD Toolbox
    \\    /   O peration     | Website:  https://openfoam.org
-    \\  /    A nd           | Copyright (C) 2021 OpenFOAM Foundation
+    \\  /    A nd           | Copyright (C) 2021-2022 OpenFOAM Foundation
      \\/     M anipulation  |
 -------------------------------------------------------------------------------
 License
@@ -109,7 +109,7 @@ Foam::tmp<Foam::fvMatrix<Type>> Foam::fvModel::source
     const GeometricField<Type, fvPatchField, volMesh>& field
 ) const
 {
-    return this->source(field, field.name());
+    return this->source(rho, field, field.name());
 }
 
 
@@ -121,7 +121,7 @@ Foam::tmp<Foam::fvMatrix<Type>> Foam::fvModel::source
     const word& fieldName
 ) const
 {
-    return source(field, fieldName, dimVolume/dimTime);
+    return source(field, fieldName, dimVolume/dimTime, rho);
 }
 
 
@@ -133,7 +133,7 @@ Foam::tmp<Foam::fvMatrix<Type>> Foam::fvModel::source
     const GeometricField<Type, fvPatchField, volMesh>& field
 ) const
 {
-    return this->source(field, field.name());
+    return this->source(alpha, rho, field, field.name());
 }
 
 
@@ -146,8 +146,81 @@ Foam::tmp<Foam::fvMatrix<Type>> Foam::fvModel::source
     const word& fieldName
 ) const
 {
-    return source(field, fieldName, dimVolume/dimTime);
+    return source(field, fieldName, dimVolume/dimTime, alpha, rho);
+}
+
+
+template<class Type>
+Foam::tmp<Foam::fvMatrix<Type>> Foam::fvModel::source
+(
+    const geometricOneField& alpha,
+    const geometricOneField& rho,
+    const GeometricField<Type, fvPatchField, volMesh>& field
+) const
+{
+    return this->source(field, field.name());
+}
+
+
+template<class Type>
+Foam::tmp<Foam::fvMatrix<Type>> Foam::fvModel::source
+(
+    const volScalarField& alpha,
+    const geometricOneField& rho,
+    const GeometricField<Type, fvPatchField, volMesh>& field
+) const
+{
+    volScalarField one
+    (
+        IOobject
+        (
+            "one",
+            this->mesh_.time().timeName(),
+            this->mesh_,
+            IOobject::NO_READ,
+            IOobject::NO_WRITE,
+            false
+        ),
+        this->mesh_,
+        dimensionedScalar(dimless, 1.0)
+    );
+
+    return this->source(alpha, one, field, field.name());
 }
 
 
+template<class Type>
+Foam::tmp<Foam::fvMatrix<Type>> Foam::fvModel::source
+(
+    const geometricOneField& alpha,
+    const volScalarField& rho,
+    const GeometricField<Type, fvPatchField, volMesh>& field
+) const
+{
+    return this->source(rho, field, field.name());
+}
+
+
+// * * * * * * * * * * * * * * Member Functions  * * * * * * * * * * * * * * //
+
+template<class Type>
+Foam::tmp<Foam::fvMatrix<Type>> Foam::fvModel::d2dt2
+(
+    const GeometricField<Type, fvPatchField, volMesh>& field
+) const
+{
+    return this->d2dt2(field, field.name());
+}
+
+
+template<class Type>
+Foam::tmp<Foam::fvMatrix<Type>> Foam::fvModel::d2dt2
+(
+    const GeometricField<Type, fvPatchField, volMesh>& field,
+    const word& fieldName
+) const
+{
+    return source(field, fieldName, dimVolume/sqr(dimTime));
+}
+
 // ************************************************************************* //