From f105d96af02372d66672d7fc71e749de707345c7 Mon Sep 17 00:00:00 2001
From: graham <g.macpherson@opencfd.co.uk>
Date: Thu, 2 Sep 2010 10:30:25 +0100
Subject: [PATCH] BUG: Fixes mantis issue 0000022: sixDoFRigidBodyMotion:
 Acceleration used as force.

---
 .../sixDoFRigidBodyMotion/sixDoFRigidBodyMotion.C  | 14 ++++++--------
 1 file changed, 6 insertions(+), 8 deletions(-)

diff --git a/src/postProcessing/functionObjects/forces/pointPatchFields/derived/sixDoFRigidBodyMotion/sixDoFRigidBodyMotion.C b/src/postProcessing/functionObjects/forces/pointPatchFields/derived/sixDoFRigidBodyMotion/sixDoFRigidBodyMotion.C
index ea47c95736..ed1e524bf6 100644
--- a/src/postProcessing/functionObjects/forces/pointPatchFields/derived/sixDoFRigidBodyMotion/sixDoFRigidBodyMotion.C
+++ b/src/postProcessing/functionObjects/forces/pointPatchFields/derived/sixDoFRigidBodyMotion/sixDoFRigidBodyMotion.C
@@ -423,23 +423,21 @@ void Foam::sixDoFRigidBodyMotion::updateForce
     scalar deltaT
 )
 {
-    vector a = vector::zero;
+    vector fGlobal = vector::zero;
 
-    vector tau = vector::zero;
+    vector tauGlobal = vector::zero;
 
     if (Pstream::master())
     {
+        fGlobal = sum(forces);
+
         forAll(positions, i)
         {
-            const vector& f = forces[i];
-
-            a += f/mass_;
-
-            tau += Q().T() & ((positions[i] - centreOfMass()) ^ f);
+            tauGlobal += (positions[i] - centreOfMass()) ^ forces[i];
         }
     }
 
-    updateForce(a, tau, deltaT);
+    updateForce(fGlobal, tauGlobal, deltaT);
 }