How to normalize a volume source in fixed source setting

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1

Hello,

I am trying to simulate the energy deposition on a sample in a reactor. The sample is placed in a tube filled with air while the tube is emerged in water. The flux inside and outside the tube is given in particle/cm2 s for neutrons and photons. I applied 4 volume sources distributed in energy according to their corresponding flux. The strength of the source correspond to the sum of the flux obtained for each energy group. I can’t figure out what should be the normalising factor to apply to a sample placed in the tube on which I measure a heating tally.

Any idea ?

2

A subproblem of mine would be to create a volume source in an homogeneous sphere of air. Given a 1 group flux, how do you normalize the output tally on that sphere ?

I believe you must somehow come up with the source strength from the flux but I cannot see how exactly.

3

Hi @azim and welcome to the community! Are you simulating this problem using the default k-eigenvalue mode or are you running in fixed source mode? Our user’s guide has a section on normalizing tally results that should be relevant.