Problem generator for advection of a field loop test. More...

Functions
void	problem (DomainS *pDomain)
	Problem initial conditions, edited for each problem.
void	problem_write_restart (MeshS pM, FILE fp)
	Problem specific subroutine for use with writing restart files, Edited for each problem.
void	problem_read_restart (MeshS pM, FILE fp)
	Problem specific subroutine for use with reading restart files, Edited for each problem.
static Real	current (const GridS *pG, const int i, const int j, const int k)
	computes x3-component of current
static Real	Bp2 (const GridS *pG, const int i, const int j, const int k)
	computes magnetic pressure (Bx2 + By2)
static Real	divB (const GridS *pG, const int i, const int j, const int k)
	calculates div(B)
static Real	Temperature (const GridS *pG, const int i, const int j, const int k)
	returns temperature for conduction tests
ConsFun_t	get_usr_expr (const char *expr)
	Sets pointer to expression for special output data.
VOutFun_t	get_usr_out_fun (const char *name)
	Returns a user defined output function pointer.
void	Userwork_in_loop (MeshS *pM)
	Problem work executed during each step in the main Athena loop, see main.c.
void	Userwork_after_loop (MeshS *pM)
	Problem work executed after the main Athena loop, see main.c Edited for each problem.

Detailed Description

Problem generator for advection of a field loop test.

PURPOSE: Problem generator for advection of a field loop test. Can only be run in 2D or 3D. Input parameters are:

problem/rad = radius of field loop
problem/amp = amplitude of vector potential (and therefore B)
problem/vflow = flow velocity
problem/drat = density ratio in loop. Enables density advection and thermal conduction tests. The flow is automatically set to run along the diagonal.

Various test cases are possible:

(iprob=1): field loop in x1-x2 plane (cylinder in 3D)
(iprob=2): field loop in x2-x3 plane (cylinder in 3D)
(iprob=3): field loop in x3-x1 plane (cylinder in 3D)
(iprob=4): rotated cylindrical field loop in 3D.
(iprob=5): spherical field loop in rotated plane

A sphere of passive scalar can be added to test advection of scalars.

The temperature in the loop can be changed using drat to test conduction.

REFERENCE: T. Gardiner & J.M. Stone, "An unsplit Godunov method for ideal MHD via constrined transport", JCP, 205, 509 (2005)

Definition in file field_loop.c.

Function Documentation

static Real Bp2	(	const GridS *	pG,
		const int	i,
		const int	j,
		const int	k
	)			`[static]`

computes magnetic pressure (Bx2 + By2)

Definition at line 361 of file field_loop.c.

References ConsS::B1c, ConsS::B2c, and GridS::U.

static Real current	(	const GridS *	pG,
		const int	i,
		const int	j,
		const int	k
	)			`[static]`

computes x3-component of current

Definition at line 353 of file field_loop.c.

References GridS::B1i, GridS::B2i, GridS::dx1, and GridS::dx2.

static Real divB	(	const GridS *	pG,
		const int	i,
		const int	j,
		const int	k
	)			`[static]`

calculates div(B)

Definition at line 369 of file field_loop.c.

References GridS::B1i, GridS::B2i, GridS::B3i, GridS::dx1, GridS::dx2, GridS::dx3, and GridS::Nx.

Referenced by problem().

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ConsFun_t get_usr_expr ( const char * expr )

Sets pointer to expression for special output data.

Definition at line 411 of file field_loop.c.

VOutFun_t get_usr_out_fun ( const char * name )

Returns a user defined output function pointer.

Definition at line 425 of file field_loop.c.

void problem ( DomainS * pDomain )

Problem initial conditions, edited for each problem.

Definition at line 42 of file field_loop.c.

References amp, ang_2, ath_error(), ConsS::B1c, GridS::B1i, ConsS::B2c, GridS::B2i, ConsS::B3c, GridS::B3i, calloc_3d_array(), cc_pos(), cos_a2, ConsS::d, GridS::dx1, GridS::dx2, GridS::dx3, ConsS::E, free_3d_array(), Gamma_1, DomainS::Grid, GridS::ie, iprob, GridS::is, GridS::je, GridS::js, GridS::ke, GridS::ks, ku, lambda, ConsS::M1, ConsS::M2, ConsS::M3, n, nx1, nx2, nx3, par_getd(), par_getd_def(), rad, DomainS::RootMaxX, DomainS::RootMinX, ConsS::s, sin_a2, GridS::U, x1c, x2c, and x3c.

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void problem_read_restart	(	MeshS *	pM,
		FILE *	fp
	)

Problem specific subroutine for use with reading restart files, Edited for each problem.

Definition at line 343 of file field_loop.c.

void problem_write_restart	(	MeshS *	pM,
		FILE *	fp
	)

Problem specific subroutine for use with writing restart files, Edited for each problem.

Definition at line 338 of file field_loop.c.

static Real Temperature	(	const GridS *	pG,
		const int	i,
		const int	j,
		const int	k
	)			`[static]`

returns temperature for conduction tests

Definition at line 397 of file field_loop.c.

void Userwork_after_loop ( MeshS * pM )

Problem work executed after the main Athena loop, see main.c Edited for each problem.

Definition at line 433 of file field_loop.c.

void Userwork_in_loop ( MeshS * pM )

Problem work executed during each step in the main Athena loop, see main.c.

Edited for each problem.

Definition at line 429 of file field_loop.c.

prob/field_loop.c File Reference

Functions

Detailed Description

Function Documentation