BurgersComputeCFL.c File Reference

Contains the function to compute maximum CFL over the domain for the Burgers equation. More...

#include <basic.h>
#include <arrayfunctions.h>
#include <physicalmodels/burgers.h>
#include <mpivars.h>
#include <hypar.h>

Go to the source code of this file.

Functions
double	BurgersComputeCFL (void *s, void *m, double dt, double t)

Detailed Description

Contains the function to compute maximum CFL over the domain for the Burgers equation.

Author

Debojyoti Ghosh

Definition in file BurgersComputeCFL.c.

Function Documentation

double BurgersComputeCFL	(	void *	s,
		void *	m,
		double	dt,
		double	t
	)

Computes the maximum CFL number over the domain. Note that the CFL is computed over the local domain on this processor only.

Parameters

s	Solver object of type HyPar
m	MPI object of type MPIVariables
dt	Time step size for which to compute the CFL
t	Time

Definition at line 15 of file BurgersComputeCFL.c.

{
  HyPar    *solver = (HyPar*)   s;
  Burgers  *params = (Burgers*) solver->physics;

  int     ndims  = solver->ndims;
  int     nvars  = solver->nvars;
  int     ghosts = solver->ghosts;
  int     *dim   = solver->dim_local;
  double  *u     = solver->u;

  int index[ndims], dir, v;

  double  max_cfl = 0;
  int done = 0; _ArraySetValue_(index,ndims,0);
  while (!done) {
    int p; _ArrayIndex1D_(ndims,dim,index,ghosts,p);
    for (v=0; v<nvars; v++) {
      for (dir=0; dir<ndims; dir++) {
        double dxinv;
        _GetCoordinate_(dir,index[dir],dim,ghosts,solver->dxinv,dxinv); /* 1/dx */
        double local_cfl = u[nvars*p+v]*dt*dxinv; 
        if (local_cfl > max_cfl) max_cfl = local_cfl;
      }
    }
    _ArrayIncrementIndex_(ndims,dim,index,done);
  }

  return(max_cfl);
}