diff --git a/applications/solvers/multiphase/compressibleMultiphaseInterFoam/multiphaseMixtureThermo/multiphaseMixtureThermo.C b/applications/solvers/multiphase/compressibleMultiphaseInterFoam/multiphaseMixtureThermo/multiphaseMixtureThermo.C
index 2161aa75a35a0205b1b8916e733ee0530bc74735..eb41aa2bbf0a217662f2b0b90ac396932875c948 100644
--- a/applications/solvers/multiphase/compressibleMultiphaseInterFoam/multiphaseMixtureThermo/multiphaseMixtureThermo.C
+++ b/applications/solvers/multiphase/compressibleMultiphaseInterFoam/multiphaseMixtureThermo/multiphaseMixtureThermo.C
@@ -6,6 +6,7 @@
      \\/     M anipulation  |
 -------------------------------------------------------------------------------
     Copyright (C) 2013-2017 OpenFOAM Foundation
+    Copyright (C) 2020 OpenCFD Ltd.
 -------------------------------------------------------------------------------
 License
     This file is part of OpenFOAM.
@@ -45,9 +46,6 @@ namespace Foam
     defineTypeNameAndDebug(multiphaseMixtureThermo, 0);
 }
 
-const Foam::scalar Foam::multiphaseMixtureThermo::convertToRad =
-    Foam::constant::mathematical::pi/180.0;
-
 
 // * * * * * * * * * * * * * Private Member Functions  * * * * * * * * * * * //
 
diff --git a/applications/solvers/multiphase/compressibleMultiphaseInterFoam/multiphaseMixtureThermo/multiphaseMixtureThermo.H b/applications/solvers/multiphase/compressibleMultiphaseInterFoam/multiphaseMixtureThermo/multiphaseMixtureThermo.H
index 18ddba8962f9542659da6ef7afc73b7b49ad5a69..368df01043d0bd8eb865b72658815b27b1892889 100644
--- a/applications/solvers/multiphase/compressibleMultiphaseInterFoam/multiphaseMixtureThermo/multiphaseMixtureThermo.H
+++ b/applications/solvers/multiphase/compressibleMultiphaseInterFoam/multiphaseMixtureThermo/multiphaseMixtureThermo.H
@@ -139,10 +139,6 @@ private:
         //- Stabilisation for normalisation of the interface normal
         const dimensionedScalar deltaN_;
 
-        //- Conversion factor for degrees into radians
-        static const scalar convertToRad;
-
-
 
     // Private member functions
 
diff --git a/src/phaseSystemModels/multiphaseEuler/multiphaseSystem/multiphaseSystem/multiphaseSystem.C b/src/phaseSystemModels/multiphaseEuler/multiphaseSystem/multiphaseSystem/multiphaseSystem.C
index dce78c2b96095f8222a95bcd5755598c932bb67f..4af3fb946791a35ba31f80ba362d19c21afbb31a 100644
--- a/src/phaseSystemModels/multiphaseEuler/multiphaseSystem/multiphaseSystem/multiphaseSystem.C
+++ b/src/phaseSystemModels/multiphaseEuler/multiphaseSystem/multiphaseSystem/multiphaseSystem.C
@@ -6,6 +6,7 @@
      \\/     M anipulation  |
 -------------------------------------------------------------------------------
     Copyright (C) 2011-2018 OpenFOAM Foundation
+    Copyright (C) 2020 OpenCFD Ltd.
 -------------------------------------------------------------------------------
 License
     This file is part of OpenFOAM.
@@ -38,11 +39,7 @@ License
 #include "fvcFlux.H"
 #include "fvcAverage.H"
 
-// * * * * * * * * * * * * * * * Static Member Data  * * * * * * * * * * * * //
-
-const Foam::scalar Foam::multiphaseSystem::convertToRad =
-    Foam::constant::mathematical::pi/180.0;
-
+#include "unitConversion.H"
 
 // * * * * * * * * * * * * * Private Member Functions  * * * * * * * * * * * //
 
@@ -281,7 +278,7 @@ void Foam::multiphaseSystem::correctContactAngle
 
             bool matched = (tp.key().first() == phase1.name());
 
-            scalar theta0 = convertToRad*tp().theta0(matched);
+            const scalar theta0 = degToRad(tp().theta0(matched));
             scalarField theta(boundary[patchi].size(), theta0);
 
             scalar uTheta = tp().uTheta();
@@ -289,8 +286,8 @@ void Foam::multiphaseSystem::correctContactAngle
             // Calculate the dynamic contact angle if required
             if (uTheta > SMALL)
             {
-                scalar thetaA = convertToRad*tp().thetaA(matched);
-                scalar thetaR = convertToRad*tp().thetaR(matched);
+                const scalar thetaA = degToRad(tp().thetaA(matched));
+                const scalar thetaR = degToRad(tp().thetaR(matched));
 
                 // Calculated the component of the velocity parallel to the wall
                 vectorField Uwall
diff --git a/src/phaseSystemModels/multiphaseEuler/multiphaseSystem/multiphaseSystem/multiphaseSystem.H b/src/phaseSystemModels/multiphaseEuler/multiphaseSystem/multiphaseSystem/multiphaseSystem.H
index 039e85a964b069e23413e5519fb4a747852dd21f..18c1cfc628229e53c2371ee9037237b8c60f88bc 100644
--- a/src/phaseSystemModels/multiphaseEuler/multiphaseSystem/multiphaseSystem/multiphaseSystem.H
+++ b/src/phaseSystemModels/multiphaseEuler/multiphaseSystem/multiphaseSystem/multiphaseSystem.H
@@ -190,9 +190,6 @@ private:
         //- Stabilisation for normalisation of the interface normal
         const dimensionedScalar deltaN_;
 
-        //- Conversion factor for degrees into radians
-        static const scalar convertToRad;
-
 
     // Private member functions
 
diff --git a/src/phaseSystemModels/reactingEuler/multiphaseSystem/multiphaseSystem/multiphaseSystem.C b/src/phaseSystemModels/reactingEuler/multiphaseSystem/multiphaseSystem/multiphaseSystem.C
index d66041e205772af4454e30d38bf4fad7623ebddd..2d67872d910ee0e3f648aa48e9dcd2c9c0250d59 100644
--- a/src/phaseSystemModels/reactingEuler/multiphaseSystem/multiphaseSystem/multiphaseSystem.C
+++ b/src/phaseSystemModels/reactingEuler/multiphaseSystem/multiphaseSystem/multiphaseSystem.C
@@ -44,6 +44,8 @@ License
 #include "fvmLaplacian.H"
 #include "fvmSup.H"
 
+#include "unitConversion.H"
+
 // * * * * * * * * * * * * * * * Static Member Data  * * * * * * * * * * * * //
 
 namespace Foam
@@ -52,9 +54,6 @@ namespace Foam
     defineRunTimeSelectionTable(multiphaseSystem, dictionary);
 }
 
-const Foam::scalar Foam::multiphaseSystem::convertToRad =
-    Foam::constant::mathematical::pi/180.0;
-
 
 // * * * * * * * * * * * * * Private Member Functions  * * * * * * * * * * * //
 
@@ -425,7 +424,7 @@ void Foam::multiphaseSystem::correctContactAngle
 
             bool matched = (tp.key().first() == phase1.name());
 
-            scalar theta0 = convertToRad*tp().theta0(matched);
+            scalar theta0 = degToRad(tp().theta0(matched));
             scalarField theta(boundary[patchi].size(), theta0);
 
             scalar uTheta = tp().uTheta();
@@ -433,8 +432,8 @@ void Foam::multiphaseSystem::correctContactAngle
             // Calculate the dynamic contact angle if required
             if (uTheta > SMALL)
             {
-                scalar thetaA = convertToRad*tp().thetaA(matched);
-                scalar thetaR = convertToRad*tp().thetaR(matched);
+                const scalar thetaA = degToRad(tp().thetaA(matched));
+                const scalar thetaR = degToRad(tp().thetaR(matched));
 
                 // Calculated the component of the velocity parallel to the wall
                 vectorField Uwall
diff --git a/src/phaseSystemModels/reactingEuler/multiphaseSystem/multiphaseSystem/multiphaseSystem.H b/src/phaseSystemModels/reactingEuler/multiphaseSystem/multiphaseSystem/multiphaseSystem.H
index f76c20117290c6ae339f670b5dfc70548f81afe3..e2f32da038025b10107c11d748216f26f8180f33 100644
--- a/src/phaseSystemModels/reactingEuler/multiphaseSystem/multiphaseSystem/multiphaseSystem.H
+++ b/src/phaseSystemModels/reactingEuler/multiphaseSystem/multiphaseSystem/multiphaseSystem.H
@@ -75,9 +75,6 @@ private:
         //- Stabilisation for normalisation of the interface normal
         const dimensionedScalar deltaN_;
 
-        //- Conversion factor for degrees into radians
-        static const scalar convertToRad;
-
 
     // Private member functions