diff --git a/applications/solvers/multiphase/driftFluxFoam/mixtureViscosityModels/BinghamPlastic/BinghamPlastic.C b/applications/solvers/multiphase/driftFluxFoam/mixtureViscosityModels/BinghamPlastic/BinghamPlastic.C
index bf9aa605ca8a79826d39cfe0834073bf38a1bd87..01826f0af476b82d4e344481b2ad52206252de78 100644
--- a/applications/solvers/multiphase/driftFluxFoam/mixtureViscosityModels/BinghamPlastic/BinghamPlastic.C
+++ b/applications/solvers/multiphase/driftFluxFoam/mixtureViscosityModels/BinghamPlastic/BinghamPlastic.C
@@ -2,7 +2,7 @@
   =========                 |
   \\      /  F ield         | OpenFOAM: The Open Source CFD Toolbox
    \\    /   O peration     |
-    \\  /    A nd           | Copyright (C) 2014 OpenFOAM Foundation
+    \\  /    A nd           | Copyright (C) 2014-2015 OpenFOAM Foundation
      \\/     M anipulation  |
 -------------------------------------------------------------------------------
 License
@@ -112,7 +112,7 @@ Foam::mixtureViscosityModels::BinghamPlastic::mu
     (
         tauy
        /(
-            mag(fvc::grad(U_))
+            sqrt(2.0)*mag(symm(fvc::grad(U_)))
           + 1.0e-4*(tauy + tauySmall)/mup
         )
       + mup,
diff --git a/applications/solvers/multiphase/driftFluxFoam/mixtureViscosityModels/BinghamPlastic/BinghamPlastic.H b/applications/solvers/multiphase/driftFluxFoam/mixtureViscosityModels/BinghamPlastic/BinghamPlastic.H
index c63bb42d82a22aac6cfe6acff820a2f4195b6701..b39f3f53e02f9f961ce2a4b5fffb34a2af69ec16 100644
--- a/applications/solvers/multiphase/driftFluxFoam/mixtureViscosityModels/BinghamPlastic/BinghamPlastic.H
+++ b/applications/solvers/multiphase/driftFluxFoam/mixtureViscosityModels/BinghamPlastic/BinghamPlastic.H
@@ -2,7 +2,7 @@
   =========                 |
   \\      /  F ield         | OpenFOAM: The Open Source CFD Toolbox
    \\    /   O peration     |
-    \\  /    A nd           | Copyright (C) 2014 OpenFOAM Foundation
+    \\  /    A nd           | Copyright (C) 2014-2015 OpenFOAM Foundation
      \\/     M anipulation  |
 -------------------------------------------------------------------------------
 License
@@ -27,6 +27,8 @@ Class
 Description
      Viscosity correction model for Bingham plastics.
 
+    The strain-rate used is defined as sqrt(2.0)*mag(symm(grad(U)))
+
 SourceFiles
     BinghamPlastic.C
 
diff --git a/applications/solvers/multiphase/driftFluxFoam/mixtureViscosityModels/mixtureViscosityModel/mixtureViscosityModel.H b/applications/solvers/multiphase/driftFluxFoam/mixtureViscosityModels/mixtureViscosityModel/mixtureViscosityModel.H
index 9b7db43f93d88f69f0a692645228b7bb9cd84690..866459ebce2e87c2749149e5e27f855aa12cbbf8 100644
--- a/applications/solvers/multiphase/driftFluxFoam/mixtureViscosityModels/mixtureViscosityModel/mixtureViscosityModel.H
+++ b/applications/solvers/multiphase/driftFluxFoam/mixtureViscosityModels/mixtureViscosityModel/mixtureViscosityModel.H
@@ -33,11 +33,6 @@ Class
 Description
     An abstract base class for incompressible mixtureViscosityModels.
 
-    The strain rate is defined by:
-
-        mag(symm(grad(U)))
-
-
 SourceFiles
     mixtureViscosityModel.C
     mixtureViscosityModelNew.C
diff --git a/tutorials/multiphase/driftFluxFoam/ras/dahl/constant/transportProperties b/tutorials/multiphase/driftFluxFoam/ras/dahl/constant/transportProperties
index 837a0af6a3375eb5832c05fd105ea5efe7abe92c..6e6819c26630cf34ed24f668c3b752e4a2cef4db 100644
--- a/tutorials/multiphase/driftFluxFoam/ras/dahl/constant/transportProperties
+++ b/tutorials/multiphase/driftFluxFoam/ras/dahl/constant/transportProperties
@@ -26,7 +26,7 @@ sludge
         coeff       0.00023143;
         exponent    179.26;
 
-        BinghamCoeff    0.00042189;
+        BinghamCoeff    0.0005966;
         BinghamExponent 1050.8;
         BinghamOffset   0;
 
diff --git a/tutorials/multiphase/driftFluxFoam/ras/mixerVessel2D/constant/transportProperties b/tutorials/multiphase/driftFluxFoam/ras/mixerVessel2D/constant/transportProperties
index 837a0af6a3375eb5832c05fd105ea5efe7abe92c..6e6819c26630cf34ed24f668c3b752e4a2cef4db 100644
--- a/tutorials/multiphase/driftFluxFoam/ras/mixerVessel2D/constant/transportProperties
+++ b/tutorials/multiphase/driftFluxFoam/ras/mixerVessel2D/constant/transportProperties
@@ -26,7 +26,7 @@ sludge
         coeff       0.00023143;
         exponent    179.26;
 
-        BinghamCoeff    0.00042189;
+        BinghamCoeff    0.0005966;
         BinghamExponent 1050.8;
         BinghamOffset   0;
 
diff --git a/tutorials/multiphase/driftFluxFoam/ras/tank3D/constant/transportProperties b/tutorials/multiphase/driftFluxFoam/ras/tank3D/constant/transportProperties
index 6af13fec407f6a23750f9e4907af7fcdbe85e70b..32ba3d76e848f51b98cd3a47ff93a79655a18b67 100644
--- a/tutorials/multiphase/driftFluxFoam/ras/tank3D/constant/transportProperties
+++ b/tutorials/multiphase/driftFluxFoam/ras/tank3D/constant/transportProperties
@@ -26,7 +26,7 @@ sludge
         coeff       0.00023143;
         exponent    0.17926;
 
-        BinghamCoeff    5.5469e-07;
+        BinghamCoeff    7.845e-07;
         BinghamExponent 95.25;
         BinghamOffset   0;