From 8e1164eeba283658db964456ca99aa639b7d75f6 Mon Sep 17 00:00:00 2001
From: Tomas Oberhuber <tomas.oberhuber@fjfi.cvut.cz>
Date: Wed, 13 Feb 2013 09:46:29 +0100
Subject: [PATCH] Adding CFL condtant to the Euler explicit ODE solver.
---
src/implementation/mesh/tnlGrid2D_impl.h | 2 +-
src/solvers/ode/tnlEulerSolver.h | 34 +++++++++++++++++++++++-
2 files changed, 34 insertions(+), 2 deletions(-)
diff --git a/src/implementation/mesh/tnlGrid2D_impl.h b/src/implementation/mesh/tnlGrid2D_impl.h
index 4977931659..f626a05f1e 100644
--- a/src/implementation/mesh/tnlGrid2D_impl.h
+++ b/src/implementation/mesh/tnlGrid2D_impl.h
@@ -250,7 +250,7 @@ bool tnlGrid< 2, Real, Device, Index> :: write( const MeshFunction& function,
for( IndexType i = 0; i < getDimensions(). x(); i++ )
{
const RealType x = this -> getLowerCorner(). x() + i * hx;
- const RealType y = this -> getLowerCorner(). y() + i * hy;
+ const RealType y = this -> getLowerCorner(). y() + j * hy;
file << x << " " << " " << y << " " << function[ this -> getNodeIndex( j, i ) ] << endl;
}
file << endl;
diff --git a/src/solvers/ode/tnlEulerSolver.h b/src/solvers/ode/tnlEulerSolver.h
index 2ae57afd7f..baf60a9467 100644
--- a/src/solvers/ode/tnlEulerSolver.h
+++ b/src/solvers/ode/tnlEulerSolver.h
@@ -37,6 +37,10 @@ class tnlEulerSolver : public tnlExplicitSolver< Problem >
tnlString getType() const;
+ void setCFLCondition( const RealType& cfl );
+
+ const RealType& getCFLCondition() const;
+
bool solve( DofVectorType& u );
protected:
@@ -46,11 +50,14 @@ class tnlEulerSolver : public tnlExplicitSolver< Problem >
DofVectorType k1;
+
+ RealType cflCondition;
};
template< typename Problem >
tnlEulerSolver< Problem > :: tnlEulerSolver()
-: k1( "tnlEulerSolver:k1" )
+: k1( "tnlEulerSolver:k1" ),
+ cflCondition( 0.0 )
{
};
@@ -62,6 +69,18 @@ tnlString tnlEulerSolver< Problem > :: getType() const
tnlString( " >" );
};
+template< typename Problem >
+void tnlEulerSolver< Problem > :: setCFLCondition( const RealType& cfl )
+{
+ this -> cflCondition = cfl;
+}
+
+template< typename Problem >
+const typename Problem :: RealType& tnlEulerSolver< Problem > :: getCFLCondition() const
+{
+ return this -> cflCondition;
+}
+
template< typename Problem >
bool tnlEulerSolver< Problem > :: solve( DofVectorType& u )
{
@@ -104,6 +123,16 @@ bool tnlEulerSolver< Problem > :: solve( DofVectorType& u )
this -> problem -> GetExplicitRHS( time, currentTau, u, k1 );
RealType lastResidue = residue;
+ RealType maxResidue( 0.0 );
+ if( this -> cflCondition != 0.0 )
+ {
+ maxResidue = k1. absMax();
+ if( currentTau * maxResidue > this -> cflCondition )
+ {
+ currentTau *= 0.9;
+ continue;
+ }
+ }
computeNewTimeLevel( u, currentTau, residue );
/****
@@ -138,6 +167,9 @@ bool tnlEulerSolver< Problem > :: solve( DofVectorType& u )
return true;
}
if( iteration == this -> getMaxIterationsNumber() ) return false;
+
+ if( this -> cflCondition != 0.0 )
+ currentTau /= 0.95;
}
};
--
GitLab