[FLASH-USERS] What variables I can put in "plot_var_N"?

[Klaus Weide]

On Tue, 9 Jun 2020, Sang Yun Shin wrote:

> I am running simulations based on LaserSlab example,
> 
> and I want to check values such as radiation flux (q_rad), electric heat
> flux (q_ele), and so on.
> 
> For check these variables, how to set a script-line  in .par file?
> 
> (In the manual, I could not find what variables I can put.)
> 
> Or, Can you tell me where there are comments or lists about what I can put?

The previous response by Ryan is right as far as it goes, for variables 
that are already defined and exist in the array of unknowns (UNK).

However, you are asking about q_rad and q_ele, which are not normally 
present in UNK. These quantities are not explicitly computed anywhere in 
the code of a LaserSlab simulation either - ultimately that is because the 
diffusion solver uses an implicit method.

So to plot those quantities, you would have to
(1) define variables to hold them in UNK (with names like "qrad" and 
    "qele"), and
(2) add code (perhaps by modifying some of the routines under 
    source/physics/Diffuse/DiffuseMain) to actually compute those
    fluxes and store them in QRAD_VAR and QELE_VAR slices of UNK.

Part (2) is nontrivial.

Some further considerations that come to mind:

* Fluxes are vector quantities, so you would probably want to store and 
  plot several components for each flux.
* The task may be easier to achieve (but, of course, also less interesting)
  in a simplified 1D configuration.


Klaus