Runtime Parameters¶
This page briefly describes parameters that may be defined in the input file. All parameters are case sensitive. Required parameters for all setups are listed first, followed by parameters required for specific Makefile flags or initial conditions. A sample parameter file can be found in the examples directory.
Todo
Port me from the wiki
Required Parameters¶
These parameters are required for all simulations
- Parameter:
nx
- Summary:
number of grid cells along the x dimension
- Type:
int
- Default:
None
- Parameter:
ny
- Summary:
number of grid cells along the y dimension
- Type:
int
- Default:
None
In a 1D problem, this must be set to 1
- Parameter:
nz
- Summary:
number of grid cells along the z dimension
- Type:
int
- Default:
None
In 1D and 2D problems, this must be set to 1
- Parameter:
xmin
- Summary:
x direction lower boundary (in code units)
- Type:
float
- Default:
None
- Parameter:
ymin
- Summary:
y direction lower boundary (in code units)
- Type:
float
- Default:
None
- Parameter:
zmin
- Summary:
z direction lower boundary (in code units)
- Type:
float
- Default:
None
Todo
Port over the remaining parameters
Chemistry¶
These parameters should all be specified in the [chemistry] parameter table.
- Parameter:
chemistry.kind
- Summary:
kind of chemistry solver to use
- Type:
str
- Default:
depends on whether you using the legacy cooling Makefile flags
This parameter specifies the choice of chemistry cooling solver. For backwards compatibility, we set the default based on the presence of Makefile parameters. When no Makefile parameters are provided, this defaults to “none.”
With the exception of “chemistry-gpu” and “grackle” (more on those in a moment), you can freely overwrite the default value at runtime. The following table summarizes the available choices (and the conditions where they become defaults):
Name |
Meaning |
Macros that make this the default |
|---|---|---|
“none” |
No chemistry or cooling |
N/A |
“tabulated-cloudy” |
path to data file used by “tabulated-cooling” solver |
|
“piecewise-cie” |
piecewise-parabolic fit to a collisional ionization equilibrium (CIE) |
|
“piecewise-ti” |
Analytic cooling/heating recipe that roughly matches the “TI” cooling runs shown in in Kim & Ostriker 2015 |
N/A |
“chemistry-gpu” |
Non-equilibrium Hydrogen/Helium chemical network with heating/cooling |
|
“grackle” |
CPU-based non-equilibrium primordial chemistry with heating/cooling |
|
Important
At the time of writing, if you want to use “chemistry-gpu,” you MUST use the CHEMISTRY_GPU Makefile parameter.
Likewise, if you want to use “grackle”, you MUST use the COOLING_GRACKLE Makefile parameter.
In both cases, we do not allow the choices to be overwritten.
- Parameter:
chemistry.data_file
- Summary:
path to data file used by “tabulated-cloudy” solver
- Type:
str
- Default:
None
It is an error to specify this parameter when chemistry.kind chemistry cooling solver other than “tabulated-cloudy.”
- Parameter:
chemistry.photoelectric_heating
- Summary:
enables photoelectric-heating
- Type:
bool
- Default:
false
Can be used to enable photoelectric-heating when chemistry.kind is set to “tabulated-cloudy” or “piecewise-ti”. It is an error to specify this for any other cooling.kind.
- Parameter:
chemistry.photoelectric_n_av_cgs
- Summary:
Parameterizes photoelectric heating
- Type:
float
- Default:
100.0
When chemistry.photoelectric_heating is true, this parameter can be used to specify the average number-density in the domain in cgs units (which is used to compute impact of photoelectric heating).
It is an error to specify this parameter when chemistry.photoelectric_heating is false.