Problem with OpenMC Simulation Using Cubit Geometry – “More than 95% of external source sites sampled were rejected” Message:

Coreform Cubit Geometry
#1

Hello Coreform team,

I exported my geometry from Coreform Cubit to use in OpenMC, but when I run the simulation, I get repeated errors:
ERROR: More than 95% of external source sites sampled were rejected.
Please check your external source’s spatial definition.
Abort(-1) on node 0 (rank 0 in comm 0): application called MPI_Abort(MPI_COMM_WORLD, -1)
Caught signal 11 (Segmentation fault)
export dagmc “model.h5m” overwrite
Could you please advise what might cause this issue?
Is there a specific export tolerance or geometry cleanup step I should apply before exporting to ensure proper source sampling in OpenMC?

I’ve attached a screenshot of the terminal output for reference.

Thank you very much for your sUploading: cubit01.cub5…
cubit01.cub5 (149.5 KB)

11
111728×618 126 KB

upport,
Fakhrulddin

#2

Whilst your problem could be the geometry, can I suggest you raise this in the OpenMC Discourse Site - https://openmc.discourse.group you will get more targeted assistance there.