Hello everyone , I am getting a ‘maximum number of lost particles has been reached’ error in code OpenMC simulation.
What is the solution to this error? “thank you for the help!
Hi Dina,
You can try the openmc geometry debug to make sure that there are no overlap cells in your geometry
‘openmc.run(geometry_debug=True)’
You can always check the documentation for troubleshooting this kind of error
Hi wahidluthfi , thank you for your reply
I ran openmc.run(geometry_debug=True) to check for geometry issues. It listed some cells, but when I checked them I didn’t find any error in the code. However, I still have a problem with the geometry and I’m not sure where exactly the issue is coming from
Have you checked your boundary condition for the outer surface of your model? If your model is a small geometry with reflective BC, then the outer surface should be reflective instead of the default transmission BC. But if the geometry has a vacuum BC for the outer surface, then only the outer surface has the vacuum BC.
Also, from the geometry debug feature of openmc, you can see if there are any overlapping cells in your model. Make sure that there are no overlapping cells or any surface with boundary conditions that are not properly defined.
Without the model itself, I can just give you a general suggestion.
Thank you for your suggestion. I checked the boundary conditions of the outer surfaces in my model. The outer boundary is defined as vacuum and the internal surfaces do not have vacuum boundary conditions. I also ran the geometry debug option in OpenMC to check for overlapping cells. However, I still get the “maximum lost particles” error. Could the issue be related to my cell regions or geometry definition?
Have all regions been defined properly? Is it a k-eigenvalue or is it a fixed source calculation?
Could you send us the model geometry to check?
Yes, I found the issue. There was a missing definition in one of the cells in the geometry. After correcting it, the error disappeared and the simulation runs correctly now. Thank you very much for your help!