hi everyone, I have an issue while doing a burnup calculation using openmc-dev, I have as an input the initial atom density of U235 equal to 2.55E-04 (at/b-cm), after running the program it gives me at 0 burnup the atom density of U235 equal to 9.92E-02 (at/b-cm)… it gives me a value more than the initial atom density …
@abdel_laouzi Can you share your material definition for the material that you are seeing problems in? One thing that comes to mind is that the atom densities in materials are renormalized by the total density, so it’s possible that the renormalization takes the value original input as 2.55e-04 and normalizes it to 9.92e-02 based on the total density.
The material definition looks fine. The renormalization to the total density does result in a change, but it is small (U235 goes from 2.55e-04 to 2.52e-04). Where do you see the value 9.92e-02? Is this what you’re getting from the depletion results file?
@abdel_laouzi By default, the get_atoms method gives you the total number of atoms by default, not an atom density. If you want an atom density in atom/b-cm, you should run, for example:
results.get_atoms('1', 'U235', nuc_units='atom/b-cm')
Note that this option was added in our latest release, 0.12.
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