two_d_unsteady_heat_t_adapt.cc File Reference

#include "generic.h"
#include "unsteady_heat.h"
#include "meshes/rectangular_quadmesh.h"

Classes
class	UnsteadyHeatProblem< ELEMENT >
	UnsteadyHeat problem. More...

Namespaces
	ExactSolnForUnsteadyHeat
	Namespace for unforced exact solution for UnsteadyHeat equation.

Functions
void	ExactSolnForUnsteadyHeat::get_exact_u (const double &time, const Vector< double > &x, Vector< double > &u)
	Exact solution as a Vector. More...
void	ExactSolnForUnsteadyHeat::get_exact_u (const double &time, const Vector< double > &x, double &u)
	Exact solution as a scalar. More...
void	ExactSolnForUnsteadyHeat::get_source (const double &time, const Vector< double > &x, double &source)
	Source function to make it an exact solution. More...
int	main (int argc, char *argv[])

Variables
double	ExactSolnForUnsteadyHeat::Gamma =10.0
	Factor controlling the rate of change. More...

Function Documentation

main()

int main	(	int argc	,
		char *	argv[]
	)

///////////////////////////////////////////////////////////////////// ///////////////////////////////////////////////////////////////////// ///////////////////////////////////////////////////////////////////// Driver code for the adaptive solution of an unsteady heat equation with option for restart from disk: Only a single command line argument is allowed. If specified it is interpreted as the name of the restart file.

{
 
 // Store command line arguments
 CommandLineArgs::setup(argc,argv);
 
 // Build problem
 UnsteadyHeatProblem<QUnsteadyHeatElement<2,4> >
  problem(&ExactSolnForUnsteadyHeat::get_source);
 
 // Setup labels for output
 DocInfo doc_info;
 
 // Output directory
 doc_info.set_directory("RESLT");
 
 // Output number
 doc_info.number()=0;
 
 // Open a trace file
 ofstream trace_file;
 char filename[100];   
 sprintf(filename,"%s/trace.dat",doc_info.directory().c_str());
 trace_file.open(filename);
 trace_file << "VARIABLES=\"time\",\"dt\",\"u<SUB>FE</SUB>\","
            << "\"u<SUB>exact</SUB>\",\"norm of error\",\"norm of solution\""
            << std::endl;
 
 // Choose simulation interval
 double t_max=0.18; // 2.0;
 
 // Set IC
 problem.set_initial_condition();
 
 
 // Initial timestep: Use the one used when setting up the initial
 // condition
 double dt=problem.time_pt()->dt();
 
 //Output initial condition
 problem.doc_solution(doc_info,trace_file);
 
 //Increment counter for solutions 
 doc_info.number()++;
 
 // Target error for adaptive timestepping
 double epsilon_t=1.0e-4;
 
 // Timestepping loop: Don't know how many steps we're going to take
 // in advance
 while (problem.time_pt()->time()<t_max)
  {
  
   // Take an adaptive timestep -- the input dt is the suggested timestep.
   // The adaptive timestepper will adjust dt until the required error
   // tolerance is satisfied. The function returns a suggestion
   // for the timestep that should be taken for the next step. This
   // is either the actual timestep taken this time or a larger
   // value if the solution was found to be "too accurate". 
   double dt_next=problem.adaptive_unsteady_newton_solve(dt,epsilon_t);
 
   // Use dt_next as suggestion for the next timestep
   dt=dt_next;
 
   //Output solution
   problem.doc_solution(doc_info,trace_file);
   
   //Increment counter for solutions 
   doc_info.number()++;
 
  } // end of timestepping loop
 
 // Close trace file
 trace_file.close();
 
 
}; // end of main

References oomph::DocInfo::directory(), MergeRestartFiles::filename, ExactSolnForUnsteadyHeat::get_source(), oomph::DocInfo::number(), problem, oomph::DocInfo::set_directory(), and Flag_definition::setup().