diff --git a/src/lagrangian/spray/submodels/BreakupModel/PilchErdman/PilchErdman.C b/src/lagrangian/spray/submodels/BreakupModel/PilchErdman/PilchErdman.C
index d900260410f2762bca73ed3d7c018ad1a844cdfa..2aca8ae5ad602142514d3aa82afea261a21adadf 100644
--- a/src/lagrangian/spray/submodels/BreakupModel/PilchErdman/PilchErdman.C
+++ b/src/lagrangian/spray/submodels/BreakupModel/PilchErdman/PilchErdman.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) 2011-2013 OpenFOAM Foundation
      \\/     M anipulation  |
 -------------------------------------------------------------------------------
 License
@@ -127,10 +127,10 @@ bool Foam::PilchErdman<CloudType>::update
 
         scalar rho12 = sqrt(rhoc/rho);
 
-        scalar Vd = Urmag*rho12*(B1_*taubBar * B2_*taubBar*taubBar);
+        scalar Vd = Urmag*rho12*(B1_*taubBar + B2_*taubBar*taubBar);
         scalar Vd1 = sqr(1.0 - Vd/Urmag);
         Vd1 = max(Vd1, SMALL);
-        scalar Ds = 2.0*Wec*sigma*Vd1/(Vd1*rhoc*sqr(Urmag));
+        scalar Ds = 2.0*Wec*sigma/(Vd1*rhoc*sqr(Urmag));
         scalar A = Urmag*rho12/d;
 
         scalar taub = taubBar/A;