Average neutron energy from the neutron spectrum using OpenMC simulations

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1

Could anyone please help me in determining the average neutron energy for the spectrum obtained using OpenMC lattice physics calculations?
I have made an attempt using ∑Ei⋅ϕi / ∑ϕi, but the resulting number appears to be unbelievable. According to the literature, the average neutron energy for PHWR is reported as 0.08 eV. Do the spectra of the lattice and core differ too much?
Kindly guide.
could you kindly let me know if average neutron energy information is available in the OpenMC .results file?

With best regards,
L Thilagam

2

Hi,
since the energy range in a reactor spectrum is at least 9 decades, energy bins in tallies are often log scaled. The sum should then rather include the size of energy bins sum(dEi * bin_average flux)/sum(bin_average flux).
And yes a Candu spectrum typically is even softer than a light water reactor spectrum.

3

Got it. Thank you very much for your kind response, sir.