sb_flux.c File Reference

Enforce conservation at the X1 boundaries in the shearing-box module. More...

#include "pluto.h"

Functions
void	SB_SaveFluxes (State_1D *state, Grid *grid)
void	SB_CorrectFluxes (Data_Arr U, double t, double dt, Grid *grid)

Variables
static double ****	FluxL
static double ****	FluxR

Detailed Description

This file provides a set of functions for storing and then modifying the upwind fluxes computed during the Riemann solver at the leftmost and righmost physical boundaries. These tasks are performed only when either SB_SYMMETRIZE_HYDRO, SB_SYMMETRIZE_EY, SB_SYMMETRIZE_EZ flags are set to YES in Src/MHD/shearingbox.h and are useful to avoid loss of conservation in the hydrodynamical variables (density, momentum, energy) and/or magnetic fields.

This is first achieved by calling the SB_SAVE_FLUXES() function during the time stepping scheme, with the purpose of storing the leftmost and rightmost conservative fluxes in the x-direction into the static arrays FluxL[] and FluxR[].

These fluxes are then subsequently used by SB_CORRECT_FLUXES() which interpolates the fluxes and properly correct leftmost and rightmost cell-centered flow quantities to ensure conservation.

The treatment of staggered magnetic field is done similarly by SB_CORRECT_EMF().

Authors

A. Mignone (migno.nosp@m.ne@p.nosp@m.h.uni.nosp@m.to.i.nosp@m.t)
G. Muscianisi (g.mus.nosp@m.ican.nosp@m.isi@c.nosp@m.inec.nosp@m.a.it)
G. Bodo (bodo@.nosp@m.oato.nosp@m..inaf.nosp@m..it)

Date

Aug 16, 2012

Function Documentation

void SB_CorrectFluxes	(	Data_Arr	U,
		double	t,
		double	dt,
		Grid *	grid
	)

Interpolate x-fluxes FLuxL and FluxR and properly correct leftmost and rightmost cells to ensure conservation.

Parameters

[in,out]	U	data array containing cell-centered quantities
[in]	t	the time step at which fluxes have to be computed
[in]	dt	the time step being used in the integrator stage
[in]	grid	pointer to array of Grid structures

Note

In parallel and if there's more than one processor in the x direction, we modify the values of FluxL and FluxR independently since the two boundary sides are handled by different processors. Conversely, when a processor owns both sides, we need to copy at least one of the two arrays before doing interpolation since their original values are lost when setting boundary conditions.

void SB_SaveFluxes	(	State_1D *	state,
		Grid *	grid
	)

Store leftmost and rightmost conservative fluxes in the x direction into FluxL and FluxR.

Parameters

[in]	state	pointer to a State_1D structure
[in]	grid	pointer to an array of Grid structures

Returns

This function has no return value.

Variable Documentation

double**** FluxL

static

Array of fluxes at the left x-boundary.

double**** FluxR

static

Array of fluxes at the right x-boundary.