From 00dc2108de54cc4ebf62c033cf9082705b419e0d Mon Sep 17 00:00:00 2001
From: Hrvoje Jasak <h.jasak@wikki.co.uk>
Date: Thu, 29 Oct 2015 15:29:08 +0000
Subject: [PATCH] Memory optimisation

---
 applications/solvers/coupled/MRFPorousFoam/UEqn.H | 10 +++++-----
 applications/solvers/coupled/MRFPorousFoam/pEqn.H |  4 +++-
 2 files changed, 8 insertions(+), 6 deletions(-)

diff --git a/applications/solvers/coupled/MRFPorousFoam/UEqn.H b/applications/solvers/coupled/MRFPorousFoam/UEqn.H
index ed0e2bc44..b9ccb0b8a 100644
--- a/applications/solvers/coupled/MRFPorousFoam/UEqn.H
+++ b/applications/solvers/coupled/MRFPorousFoam/UEqn.H
@@ -1,5 +1,5 @@
     // Momentum equation
-    fvVectorMatrix UEqn
+    tmp<fvVectorMatrix> UEqn
     (
         fvm::ddt(U)
       + fvm::div(phi, U)
@@ -7,9 +7,9 @@
     );
 
     // Add MRF and porous sources
-    mrfZones.addCoriolis(UEqn);
-    pZones.addResistance(UEqn);
+    mrfZones.addCoriolis(UEqn());
+    pZones.addResistance(UEqn());
 
-    UEqn.relax();
+    UEqn().relax();
 
-    UpEqn.insertEquation(0, UEqn);
+    UpEqn.insertEquation(0, UEqn());
diff --git a/applications/solvers/coupled/MRFPorousFoam/pEqn.H b/applications/solvers/coupled/MRFPorousFoam/pEqn.H
index 9029b873f..134b264d4 100644
--- a/applications/solvers/coupled/MRFPorousFoam/pEqn.H
+++ b/applications/solvers/coupled/MRFPorousFoam/pEqn.H
@@ -2,9 +2,11 @@
 surfaceScalarField rUAf
 (
     "rUAf",
-    fvc::interpolate(1.0/UEqn.A())
+    fvc::interpolate(1.0/UEqn().A())
 );
 
+UEqn.clear();
+
 surfaceScalarField presSource
 (
     "presSource",