LinearADRJacobian.c File Reference

Function to compute the hyperbolic flux Jacobian for the linear advection-diffusion-reaction system. More...

#include <mathfunctions.h>
#include <physicalmodels/linearadr.h>

Go to the source code of this file.

Functions
int	LinearADRAdvectionJacobian (double *Jac, double *u, void *p, int dir, int nvars, int upw)
int	LinearADRDiffusionJacobian (double *Jac, double *u, void *p, int dir, int nvars)

Detailed Description

Function to compute the hyperbolic flux Jacobian for the linear advection-diffusion-reaction system.

Author

Debojyoti Ghosh

Definition in file LinearADRJacobian.c.

Function Documentation

LinearADRAdvectionJacobian()

int LinearADRAdvectionJacobian	(	double *	Jac,
		double *	u,
		void *	p,
		int	dir,
		int	nvars,
		int	upw
	)

Function to compute the flux Jacobian for the hyperbolic (advection) part of the linear-advection-diffusion-reaction model.

Parameters

Jac	Jacobian matrix of size 1 (nvar = 1)
u	solution at a grid point
p	object containing physics-related parameters
dir	dimension (x/y/z)
nvars	number of components
upw	0 -> send back complete Jacobian, 1 -> send back Jacobian of right(+)-moving flux, -1 -> send back Jacobian of left(-)-moving flux

Definition at line 11 of file LinearADRJacobian.c.

{
  LinearADR *param = (LinearADR*) p;

  if (param->a) {
    *Jac =    (1-absolute(upw))*absolute(param->a[dir])
           +  absolute(upw) * (1+upw) * max(0,param->a[dir]) * 0.5
           -  absolute(upw) * (1-upw) * min(0,param->a[dir]) * 0.5 ;
  } else {
    /* no advection term */
    *Jac = 0.0;
  }

  return 0;
}

LinearADRDiffusionJacobian()

int LinearADRDiffusionJacobian	(	double *	Jac,
		double *	u,
		void *	p,
		int	dir,
		int	nvars
	)

Function to compute the Jacobian for the parabolic (diffusion) part of the linear-advection-diffusion-reaction model.

Parameters

Jac	Jacobian matrix of size 1 (nvar = 1)
u	solution at a grid point
p	object containing physics-related parameters
dir	dimension (x/y/z)
nvars	number of components

Definition at line 36 of file LinearADRJacobian.c.

{
  LinearADR *param = (LinearADR*) p;

  int v;
  for (v = 0; v < nvars; v++) {
    Jac[nvars*v+v] = -param->d[nvars*dir+v];
  }

  return 0;
}