Search found 5 matches

by francois.vh
Tue Feb 04, 2014 1:41 pm
Forum: Development
Topic: Microscopic cross section generation
Replies: 1
Views: 979

Microscopic cross section generation

Is it possible to add some microscopic cross sections to the broad group cross sections generated per universe? In particular, in order to deplete with our core simulator, we require: (LaTeX markup) \int dr\int dE N_i(r) \sigma_i^t(r,E) \theta(r,E) / ( N_i * \int dr \int dE \theta(r,E) ) where : N_i...
by francois.vh
Wed Nov 13, 2013 2:38 pm
Forum: Bugs, problems, questions & feeback
Topic: Strange behaviour of heavy absorbers in non fuel assemblies
Replies: 7
Views: 3029

Re: Strange behaviour of heavy absorbers in non fuel assemblies

I've noticed that Serpent 2 runs a LOT slower with dt set to 1. Is this behaviour expected?
by francois.vh
Tue Nov 12, 2013 3:44 pm
Forum: Bugs, problems, questions & feeback
Topic: Strange behaviour of heavy absorbers in non fuel assemblies
Replies: 7
Views: 3029

Re: Strange behaviour of heavy absorbers in non fuel assemblies

Actually, dt 1 seems to give the correct answer. It gets progressively worse when you reduce dt, and at dt 0 it crashes with a fission source error : either "Unable to initiate self-sustaining chain reaction" or "WTF" :) I'll test dt 1 on the larger problems (which has type 11 lattices) and see if I...
by francois.vh
Tue Nov 12, 2013 10:19 am
Forum: Bugs, problems, questions & feeback
Topic: Strange behaviour of heavy absorbers in non fuel assemblies
Replies: 7
Views: 3029

Strange behaviour of heavy absorbers in non fuel assemblies

Serpent 2 does not seem to treat heavy absorbers in assemblies without fissile material correctly. The result (input included below) is about 1200 pcm lower than MCNP and Serpent 1. I don't think its the absorber material or geometry, since I've done numerous calculations with absorbers imbedded in ...
by francois.vh
Thu Jul 26, 2012 3:20 pm
Forum: Bug reports
Topic: Current detector and boundary conditions
Replies: 1
Views: 2522

Current detector and boundary conditions

There seems to be a problem with the current detector in the presence of reflective boundary conditions. I tested the detector in a simple cuboid geometry, and calculated the current over a surface splitting the cuboid in half. The surface is perpendicular to all but two of the reflective surfaces. ...