Questions on Depletion

Hello, I am running a basic simulation of a discrete neutron source impacting a spherical shell of pure cobalt. I am running a depletion model to track the concentration of the cobalt nuclides during and after “operation,” i.e. while the source is active.

  1. If I choose to set a source rate instead of power and use this as my normalization mode, is this value distinct from the source strength I have chosen in my source settings? For instance, if I have set my source strength as 1.0, could I also set my source rate to 1.0, or would I have to multiply by the number of source particles? (As I understand, the source strength is normalized to the number of source particles.)

  2. If I instead set my normalization mode to ‘energy-deposition’, my simulation runs, but no depletion_results.h5 file is created. I don’t understand why this might happen. Does this mode only work in the presence of fissile material in the model?

  3. Depletion requires the user to state the volume of the depletable material, but I have already provided the radius of the sphere and thickness of the shell in the problem geometry. What is the purpose of requiring the user to calculate the volume of the material when OpenMC can already calculate this using the given parameters?