collapsible_channel.cc File Reference

#include <iostream>
#include "generic.h"
#include "navier_stokes.h"
#include "meshes/collapsible_channel_mesh.h"

Classes
class	OscillatingWall
class	CollapsibleChannelProblem< ELEMENT >
	Problem class. More...

Namespaces
	BL_Squash
	Global_Physical_Variables
	Global variables.

Functions
double	BL_Squash::squash_fct (const double &s)
void	Global_Physical_Variables::prescribed_traction (const double &t, const Vector< double > &x, const Vector< double > &n, Vector< double > &traction)
	Traction applied on the fluid at the left (inflow) boundary. More...
int	main (int argc, char *argv[])

Function Documentation

main()

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

Driver code for an unsteady adaptive collapsible channel problem with prescribed wall motion. Presence of command line arguments indicates validation run with coarse resolution and small number of timesteps.

{
 
 // Store command line arguments
 CommandLineArgs::setup(argc,argv);
  
 // Reduction in resolution for validation run?
 unsigned coarsening_factor=1;
 if (CommandLineArgs::Argc>1)
  {
   coarsening_factor=4;
  }
 
 // Number of elements in the domain
 unsigned nup=20/coarsening_factor;
 unsigned ncollapsible=40/coarsening_factor;
 unsigned ndown=40/coarsening_factor;
 unsigned ny=16/coarsening_factor;
 
 // Length of the domain
 double lup=5.0;
 double lcollapsible=10.0;
 double ldown=10.0;
 double ly=1.0;
 
 // Initial amplitude of the wall deformation
 double amplitude=1.0e-2; // ADJUST 
  
 // Period of oscillation
 double period=0.45;
 
 // Pressure/applied traction on the left boundary: This is consistent with 
 // steady Poiseuille flow
 Global_Physical_Variables::P_up=12.0*(lup+lcollapsible+ldown);
 
 
 //Set output directory
 DocInfo doc_info;
 doc_info.set_directory("RESLT");
 
 // Open a trace file 
 ofstream trace_file;
 char filename[100];   
 sprintf(filename,"%s/trace.dat",doc_info.directory().c_str());
 trace_file.open(filename);
 
 // Build the problem with Crouzeix Raviart Elements
 CollapsibleChannelProblem<RefineableQCrouzeixRaviartElement<2> > 
  problem(nup, ncollapsible, ndown, ny, 
          lup, lcollapsible, ldown, ly, 
          amplitude,period);
 
 
 // Number of timesteps per period
 unsigned nsteps_per_period=40;
 
 // Number of periods
 unsigned nperiod=3; 
 
 // Number of timesteps (reduced for validation)
 unsigned nstep=nsteps_per_period*nperiod;
 if (CommandLineArgs::Argc>1)
  {
   nstep=3;
  }
 
 //Timestep: 
 double dt=period/double(nsteps_per_period);
 
 // Start time
 double t_min=0.0;
 
 // Initialise timestep and set initial conditions
 problem.time_pt()->time()=t_min;
 problem.initialise_dt(dt);
 problem.set_initial_condition();
 
  // Output the initial solution
 problem.doc_solution(doc_info, trace_file);
 
 // Step number
 doc_info.number()++;
 
 
 // Set targets for spatial adaptivity
 problem.bulk_mesh_pt()->max_permitted_error()=1.0e-3;
 problem.bulk_mesh_pt()->min_permitted_error()=1.0e-5;
 
 // Overwrite with reduced targets for validation run to force
 // some refinement during the first few timesteps
 if (CommandLineArgs::Argc>1)
  {
   problem.bulk_mesh_pt()->max_permitted_error()=1.0e-4;
   problem.bulk_mesh_pt()->min_permitted_error()=1.0e-6;
  }
 
 
 // First timestep: We may re-assign the initial condition
 // following any mesh adaptation.
 bool first=true;
 
 // Max. number of adaptations during first timestep
 unsigned max_adapt=10;
 
 // Timestepping loop
 for (unsigned istep=0;istep<nstep;istep++)
  {
   // Solve the problem
   problem.unsteady_newton_solve(dt, max_adapt, first);
    
 
   // Outpt the solution
   problem.doc_solution(doc_info, trace_file);
   
   // Step number
   doc_info.number()++;
 
   // We've done one step: Don't re-assign the initial conditions
   // and limit the number of adaptive mesh refinements to one
   // per timestep.
   first=false;
   max_adapt=1;
  }
 
 trace_file.close();
 
} //end of driver code

References oomph::CommandLineArgs::Argc, oomph::DocInfo::directory(), MergeRestartFiles::filename, Mesh_Parameters::ly, oomph::DocInfo::number(), Mesh_Parameters::ny, Global_Physical_Variables::P_up, problem, oomph::DocInfo::set_directory(), and Flag_definition::setup().