PDA

View Full Version : ENDF (ACE) Cross-sections?


laxsu19
Mar2-09, 06:07 PM
Hi all,
I've noticed there are a few PhDs on this board whose experience I'd like to leverage. For my masters thesis I am writing a monte carlo transport code from scratch. The end goal of this work is to examine the feasibility of porting the code to a GPGPUs. I chose to write the code from scratch because to effectively do my work I would have to fully understand all aspects of the MC code, something I know I couldnt manage with something like MCNP. I have one more problem to solve before I can consider myself to have a functioning code: cross-sections.

When attacking these cross-sections, I would like to have a true point-wise cross-section set, including anisotropic scattering. Is this a reasonable goal? I have been studying the ENDF and MCNP manuals, trying to decipher the ACE format code, but it seems like an implementation of such would be a thesis in itself.

There are simplifying assumptions I could make (ignore anisotropic scattering, use group cross-sections as opposed to point-wise, or simply just use 1-group cross-sects), but in order to fully understand possible speedups a GPGPU could provide I should at least have a more accurate set of calculations that need to be performed.

Any suggestions? Thanks in advance all.

laxsu19
Mar2-09, 06:14 PM
p.s. I think the BEST solution would be if there was a library out there to do this for me (I am writing in C/C++ btw), not sure I know of one on the RSICC, or even sourceforge for that matter.

QuantumPion
Mar3-09, 02:45 PM
The new versions of SCALE use point-wise continuous energy cross sections contained in the ENDFB/VI and VII libraries. They use a fortran program called AMPX-2000 to process their working libraries. There's a short paper on it here: http://nsdl.org/resource/2200/20061005035357508T

P.S., let me know if you are successful in your research! I would love to run monte carlo problems on my home computer with its powerful video card compared to my slow office machine :D

laxsu19
Mar7-09, 08:39 AM
Thanks for the info. I read that paper you linked to, AMPX isnt a data access code though is it? It sort of works more like NJOY (but in a way that scale wants) as far as I can tell. Is that the case?