[FLASH-USERS] Troubles with BDRY variable and UHD (FLASH4.2.1)

[dongwook at flash.uchicago.edu]

Hi Morgan,

What you need is to initialize BDRY_VAR in your Simulation_initBlock.F90
properly, that is,

  BDRY_VAR to be -1.0 for gas (or fluid) cells,
  BDRY_VAR to be   1.0 for stationary solid cells.


Without this initialization, the code will assume BDRY_VAR initially zero
everywhere, and this will tell the hydro routines that everywhere is
treated as non-gas and hydro routines will skip all of the relevant
calculations on those cells. This is why the code crashes.

Please do this initialization and let me know how it works.

Best,
Dongwook
=========================================
Dongwook Lee, Ph.D., Research Scientist
The Flash Center for Computational Science
The University of Chicago
5747 S. Ellis Ave., Room 319
Chicago, IL 60637
(773) 834-6830

> Dear all,
>
> I encountered an issue in moving a setup I have been working with from
> FLASH4.0.1 to FLASH4.2.1. I'm hoping someone here can point out where I'm
> going wrong in adopting the new UHD module.
>
> I found that the unsplit hydro option
> order=3
> would lead to a segmentation fault at the very first timestep in 3D
> simulations in which a BDRY variable is being used to create a solid
> boundary. With order=2, the simulation runs.
>
> I backtracked a bit and am able to reproduce the problem I'm having most
> simply by starting with the Sedov setup:
> ./setup Sedov -3d -auto +uhd +pm4dev
> works fine with the default flash.par (which calls for order=3).
>
> If I edit the Config file of Sedov to include a variable BDRY (by adding
> the a line "VARIABLE BDRY" to the end of the file), but make no other
> changes, the code crashes during the first timestep (with a seg fault).
>
> If I then set order=2, the code appears to run.
>
> Similarly, if the setup is in 2D no issues present themselves.
>
> I am using ifort  14.0.1 to compile.  Perhaps I am passing some
> conflicting
> options in my setup line? Or maybe this is a bug? Either way, I'm hoping
> someone can advise me on how to proceed. Let me know if more information
> would be useful.
>
> Thank you for the help!
>
> Morgan
>