Problem associating the materials created in openmc with geometry imported using dagmc universe

User Support
1

I am not able to associate the materials created with openmc with the geometry imported with dagmc universe. I would appreciate any help regarding this issue. Here are some details of the process I follow.

  1. Creation of the geometry in CATIA and exported to stp file. Then I use a funcion cad_to_dagmc
    to convert the stp file to the dagmc model (format h5m), and assign the corresponding material tags to each volume:

  2. Creation of the materials in openmc, defining properties with the same materials names that the materials tags created in the dagmc file.

  3. Import dagmc model. With pydagmc, I observed that the materials tags of the imported h5m file coincide with the material names defined. I used this function:
    dag_univ = openmc.DAGMCUniverse(filename = ‘dagmc.h5m’, auto_geom_ids=True, auto_mat_ids=True)
    print(dag_univ.material_names)

  4. Create a cell containing the universe:
    vac = openmc.Sphere(r=2500, boundary_type=“vacuum”)
    container = openmc.Cell(region=-vac, fill=dag_univ)
    geometry = openmc.Geometry([container])

The tallies do not recognize when i try to use a filter by material but no reactions occur. I have tried to plot the geometry by material, and use the volume function from openmc to estimate the volumes and both of them work perfectly. Even, when I use flux tallies or heating tallies with a mesh filters, it recognized the volume and I am obtaining some results.

However when I try to use a material filter to calculate for example the H3 production, I am not getting any result. I would be happy to provide any script or file if required.

Best regards,
Jose