Problem with multiple fire meshes and evac mesh

[Lucas Monnin]

Dear forum,

I have a problem using multiple fire meshes with an evacuation mesh. Basically, I have a few meshes connected together along X-direction (a tunnel), and just another mesh on top of two of them (corresponding to an opening on the tunnel ceiling). An evacuation mesh is also used along the tunnel.

When I try to run it on multiple mpi (8), I get the "forrtl: severe (157): Program Exception - access violation" error.

I tried a few other configurations, that all worked:

• Single MPI
• Only the fire meshes (no evacuation mesh) on multiple mpi (7)
• tunnel meshes and evacuation mesh (no ceiling opening mesh) on multiple mpi (8)
• All meshes on multiple MPI, but 7 MPI instead of 8

The fact that the last test described above worked is totally inexplicable for me!

Any explication?

Please find the code attached.

Regards,

Lucas

[TimoK]

Are you using FDS 6.7.6? If so, see:https://github.com/tkorhon1/FDS-Evac-Guide/blob/master/Manual/Readme.txt

Well, it might be that the readme file is for FDS 6.7.5, and 6.7.6 has a more user friendly way of doing things (search EVACUATION_ALL_STEPS in this forum).

Note, that your evacuation mesh has just 2 grid cells in the x-direction.

If you are using FDS 6.7.6:

EVACUATION_INITIALIZATION=.TRUE. phase: run just with one process (only evacuation meshes in the calculation)

EVACUATION_WRITE_FED=.TRUE. phase: run as a fire calculation without any evacuation (in your case 5 processes)

EVACUATION_MC_MODE=.TRUE. phase: run just with one process (only evacuation meshes in the calculation)

If you are using FDS6.7.5

EVACUATION_DRILL=.FALSE., EVACUATION_MC_MODE=.FALSE. : number of processes = number of fire processes + 1

And with EVACUATION_DRILL=.TRUE. and/or EVACUATION_MC_MODE=.TRUE. number of processes = 1.

TimoK