Flux tally value lowest margin.

Hello, When tallying flux in a small volume, I believe openmc is not considering the tally value if the value is less than e-06-e-07. I believe if the value is below than that, The tally shows 0.

How to increase this margin if this is set in and from where?

Hi Sharif,

There is no lower limit on a score that may be tallied. What you may be observing is that if you make some cell in your problem smaller and smaller, the number of particles that contribute to that tally will also decrease. Eventually, if the volume is small enough, you’ll end up with zero particles contributing to the tally and hence a score of zero. If you run more particles for such a model, eventually you’ll see a positive score in the tally.

Best regards,
Paul

Dr, Thanks for the information. I see my mistake Currently I was running 3000 particles and 3000 batches, with 50 inactive. I will try increasing the particles on my run. Tanks for the reply. Great help.