Hydro_InitExcision - Initial Excision for Hydro Evolutions

Andrea Nerozzi, Frank Löffler

April 20, 2017

Abstract

This thorn initialises the excision-spacemask for GRHydro to specified forms. It is based on a similar version used to initialise the excision-mask for Whisky code.

1 Using This Thorn

Using this thorn is quite easy: You have to activate it in your parameter file and specify at least the following:

hydro_initexcision::hydro_initexcision = "yes"

In addition to that you may want to specify the type of excision zone you want to have. You can do this by

hydro_initexcision::hydro_initexcision_type = <TYPE>

where

<TYPE>

is one of the following list:

2 Thorn Source Code

This was initially written by Andrea Nerozzi and later changed by Frank Löffler.

3 Thorn Documentation

This documentation was largely written by Frank Löffler.

4 Parameters




hydro_initexcision
Scope: restricted  BOOLEAN



Description: Sets up an excision zone



  Default: no






hydro_initexcision_coordinate_length
Scope: restricted  REAL



Description: Length of excised region



Range   Default: (none)
0:
Length of excised region, has different meanings for the types






hydro_initexcision_flip
Scope: restricted  INT



Description: Exchange excised and normal region



Range   Default: (none)
0:1
0 (default) for no, 1 for yes






hydro_initexcision_fraction
Scope: restricted  REAL



Description: Fraction of excised region



Range   Default: 0.25
0:1
Represents the fraction of excised region (0..1)






hydro_initexcision_min_points
Scope: restricted  INT



Description: minimal number of points of excision



Range   Default: (none)
0:
minimal number of points of excision, currently only partly implemented






hydro_initexcision_old_mask
Scope: restricted  INT



Description: Also set the old ’emask’?



Range   Default: (none)
0:1
0 (default) for no, 1 for yes






hydro_initexcision_position_x
Scope: restricted  REAL



Description: x-coordinate



Range   Default: 0.0
:
anything real is ok






hydro_initexcision_position_y
Scope: restricted  REAL



Description: y-coordinate



Range   Default: 0.0
:
anything real is ok






hydro_initexcision_position_z
Scope: restricted  REAL



Description: z-coordinate



Range   Default: 0.0
:
anything real is ok






hydro_initexcision_poststep
Scope: restricted  BOOLEAN



Description: Schedule also at poststep



  Default: no






hydro_initexcision_type
Scope: restricted  KEYWORD



Description: Type of excision to apply



Range   Default: x-axis
box
Box excised region
x-axis
X axis excision
y-axis
Y axis excision
z-axis
Z axis excision
diagonal
diagonal excision
sphere
sphere excision






domain
Scope: shared from GRID KEYWORD



5 Interfaces

General

Implements:

hydro_initexcision

Inherits:

hydrobase

grid

spacemask

6 Schedule

This section lists all the variables which are assigned storage by thorn EinsteinInitialData/Hydro_InitExcision. Storage can either last for the duration of the run (Always means that if this thorn is activated storage will be assigned, Conditional means that if this thorn is activated storage will be assigned for the duration of the run if some condition is met), or can be turned on for the duration of a schedule function.

Storage

NONE

Scheduled Functions

CCTK_INITIAL

  hydro_initexcisionmask

  sets up the excision mask

 

 After: maskone
  Language:c
 Type: function

CCTK_POST_RECOVER_VARIABLES

  hydro_initexcisionmask

  sets up the excision mask

 

 After: maskone
  Language:c
 Type: function

CCTK_POSTREGRID

  hydro_initexcisionmask

  sets up the excision mask

 

 After: maskone
  Language:c
 Type: function

CCTK_POSTSTEP

  hydro_initexcisionmask_poststep

  sets up the excision mask

 

 Before: setup_epsdis
 Language:c
 Type: function