ID_Converter_ILGRMHD: A Module for Converting HydroBase Initial Data into Variables IllinoisGRMHD Can Read

Original author: Zachariah B. Etienne.

\( \)Date: 2015-10-12 12:00:00 -0600 (Mon, 12 Oct 2015) \( \)

Abstract

IllinoisGRMHD and HydroBase variables are incompatible; The former uses 3-velocity defined as \(v^i = u^i/u^0\), and the latter uses the Valencia formalism definition of \(v^i\).

Define the Valencia formalism’s definition of \(v^i\) to be ”\(W^i\)”, and IllinoisGRMHD’s definition ”\(v^i\)” Then \begin {equation} W^i = (v^i + \beta ^i) / (\alpha ), \end {equation} which comes from Eq 11 in the IllinoisGRMHD code announcement paper:
http://arxiv.org/pdf/1501.07276.pdf.

Similarly, \begin {equation} v_i = (\alpha ) W^i - \beta ^i \end {equation}

In addition, IllinoisGRMHD needs the A-fields to be defined on staggered grids, and HydroBase does not yet support this option. The staggerings are defined in Table 1 of the IllinoisGRMHD code announcement paper:
http://arxiv.org/pdf/1501.07276.pdf (page 15).

The long-term goal should be to adjust HydroBase and IllinoisGRMHD so that this thorn is no longer necessary.

1 Parameters

gamma_initial
Scope: private  REAL
Description: Single Gamma-law EOS: Gamma
Range   Default: 1.3
0:*
Positive or zero

k_initial
Scope: private  REAL
Description: Single Gamma-law EOS: K
Range   Default: 1.0
0:*
Positive or zero

pure_hydro_run
Scope: private  BOOLEAN
Description: Set the vector potential and corresponding EM gauge quantity to zero
  Default: no

random_pert
Scope: private  REAL
Description: Random perturbation atop data
Range   Default: (none)
*:*
Anything goes.

random_seed
Scope: private  INT
Description: Random seed for random, generally roundoff-level perturbation on initial data. Seeds srand(), and rand() is used for the RNG.
Range   Default: (none)
0:99999999
Anything unsigned goes.

2 Interfaces

General

Implements:

id_converter_ilgrmhd

3 Schedule

This section lists all the variables which are assigned storage by thorn WVUThorns/ID_converter_ILGRMHD. 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