LinearADRDiffusion.c File Reference

Function to evaluate the diffusion term in the linear advection-diffusion-reaction model. More...

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

Go to the source code of this file.

Functions
int	LinearADRDiffusionG (double *f, double *u, int dir, void *s, double t)
int	LinearADRDiffusionH (double *f, double *u, int dir1, int dir2, void *s, double t)

Detailed Description

Function to evaluate the diffusion term in the linear advection-diffusion-reaction model.

Author

Debojyoti Ghosh

Definition in file LinearADRDiffusion.c.

Function Documentation

LinearADRDiffusionG()

int LinearADRDiffusionG	(	double *	f,
		double *	u,
		int	dir,
		void *	s,
		double	t
	)

Evaluate the diffusion term in the linear advection-diffusion-reaction model for a "pure Laplacian" type operator (no cross derivatives):
Compute

\begin{equation} \nu_d u \end{equation}

given \(u\) and \(d\) in the parabolic term

\begin{equation} \sum_d \frac {\partial^2} {\partial x_d^2} \left( \nu_d u \right) \end{equation}

Parameters

f	Array to hold the computed diffusion term (same size and layout as u)
u	Array containing the solution
dir	Spatial dimension (unused since this is a 1D system)
s	Solver object of type HyPar
t	Current time

Definition at line 26 of file LinearADRDiffusion.c.

{
  HyPar     *solver = (HyPar*)     s;
  LinearADR *param  = (LinearADR*) solver->physics;
  int       i, v;

  int *dim    = solver->dim_local;
  int ghosts  = solver->ghosts;
  int ndims   = solver->ndims;
  int nvars   = solver->nvars;
  int index[ndims], bounds[ndims], offset[ndims];

  /* set bounds for array index to include ghost points */
  _ArrayCopy1D_(dim,bounds,ndims);
  for (i=0; i<ndims; i++) bounds[i] += 2*ghosts;

  /* set offset such that index is compatible with ghost point arrangement */
  _ArraySetValue_(offset,ndims,-ghosts);

  int done = 0; _ArraySetValue_(index,ndims,0);
  while (!done) {
    int p; _ArrayIndex1DWO_(ndims,dim,index,offset,ghosts,p);
    for (v = 0; v < nvars; v++) f[nvars*p+v] = param->d[nvars*dir+v] * u[nvars*p+v];
    _ArrayIncrementIndex_(ndims,bounds,index,done);
  }

  return(0);
}

LinearADRDiffusionH()

int LinearADRDiffusionH	(	double *	f,
		double *	u,
		int	dir1,
		int	dir2,
		void *	s,
		double	t
	)

Evaluate the diffusion term in the linear advection-diffusion-reaction model for a parabolic operator with no cross derivatives:
Compute

\begin{equation} \nu_d u \end{equation}

given \(u\) and \(d_1,d_2\) in the parabolic term

\begin{equation} \sum_{d_1}\sum_{d_2} \frac {\partial^2} {\partial x_{d_1} \partial x_{d_2}} \left( \nu_d u \right) \end{equation}

Note: it's not correctly implemented. Will implement when necessary.

Parameters

f	Array to hold the computed diffusion term (same size and layout as u)
u	Array containing the solution
dir1	First spatial dimension of the double derivative \(d_1\)
dir2	Second spatial dimension of the double derivative \(d_2\)
s	Solver object of type HyPar
t	Current time

Definition at line 74 of file LinearADRDiffusion.c.

{
  HyPar     *solver = (HyPar*)     s;
  LinearADR *param  = (LinearADR*) solver->physics;
  int       i, v;

  int *dim    = solver->dim_local;
  int ghosts  = solver->ghosts;
  int ndims   = solver->ndims;
  int nvars   = solver->nvars;
  int index[ndims], bounds[ndims], offset[ndims];

  if (dir1 == dir2) {

    int dir = dir1;

    /* set bounds for array index to include ghost points */
    _ArrayCopy1D_(dim,bounds,ndims);
    for (i=0; i<ndims; i++) bounds[i] += 2*ghosts;

    /* set offset such that index is compatible with ghost point arrangement */
    _ArraySetValue_(offset,ndims,-ghosts);

    int done = 0; _ArraySetValue_(index,ndims,0);
    while (!done) {
      int p; _ArrayIndex1DWO_(ndims,dim,index,offset,ghosts,p);
      for (v = 0; v < nvars; v++) f[nvars*p+v] = param->d[nvars*dir+v] * u[nvars*p+v];
      _ArrayIncrementIndex_(ndims,bounds,index,done);
    }

  } else _ArraySetValue_(f,solver->npoints_local_wghosts*nvars,0.0);


  return(0);
}