Tally give zero values on ADS problem

User Support
1

Dear Openmc experts,

I am doing flux calculation on my ADS problem which external source has been used, I have tally flux in fuel_cell and coolant_cell and I got tallie.out fine but the values came all zeroes. I thought it was a problem with my external source(attached below), but I still not sure about my tallie. Would it bother if you could check my tallie?

Edited: I’ve tried to replace the external source with a uniform source bound box and finally, the flux is not zero anymore!!. But I still confuse about using an external source, please give me a suggestion.

This is what I use for replacing an external source:
bounds = [-155, -155, -155, 155, 155, 155]
uniform_dist = openmc.stats.Box(bounds[:3], bounds[3:], only_fissionable=True)
settings.source = openmc.Source(space=uniform_dist)

ads_prob.py (7.4 KB)
my tallies output
my external source

Edited script:
tally output (not external source)
new_try_ads.py (7.6 KB)
Thanks in advance,
Thanapong

2

I took a look at your script and noticed at least two problem. First, to specify a file source you should use either

source = openmc.Source(filename=...)

# ...or...
source = openmc.Source()
source.file = ...

The other problem is that it looks like the energies you’ve specified in the energy filter are in units of MeV. OpenMC uses default units of eV and will interpret these as eV, so the maximum energy is 25 eV.