Windowed multipole for cross section Doppler broadening
Name
Forget_Windowed multipole.pdf
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883.59 KB
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Adobe PDF
Checksum (MD5)
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Author(s)
Josey, Colin
Ducru, Pablo Philippe
Forget, Benoit Robert Yves
Smith, Kord S.
Date Issued
August 2015
Journal
Journal of Computational Physics
Publisher
Elsevier BV
Citation
Josey, C. et al. “Windowed Multipole for Cross Section Doppler Broadening.” Journal of Computational Physics 307 (February 2016): 715–727 © 2015 Elsevier Inc
Version
Author's final manuscript
Abstract
This paper presents an in-depth analysis on the accuracy and performance of the windowed multipole Doppler broadening method. The basic theory behind cross section data is described, along with the basic multipole formalism followed by the approximations leading to windowed multipole method and the algorithm used to efficiently evaluate Doppler broadened cross sections. The method is tested by simulating the BEAVRS benchmark with a windowed multipole library composed of 70 nuclides. Accuracy of the method is demonstrated on a single assembly case where total neutron production rates and U238 capture rates compare within 0.1% to ACE format files at the same temperature. With regards to performance, clock cycle counts and cache misses were measured for single temperature ACE table lookup and for windowed multipole. The windowed multipole method was found to require 39.6% more clock cycles to evaluate, translating to a 7.9% performance loss overall. However, the algorithm has significantly better last-level cache performance, with 3 fewer misses per evaluation, or a 65% reduction in last-level misses. This is due to the small memory footprint of the windowed multipole method and better memory access pattern of the algorithm. Keywords: Monte Carlo; Multipole; Doppler broadening
MIT Department
Massachusetts Institute of Technology. Department of Nuclear Science and Engineering
Terms of Use
Creative Commons Attribution-NonCommercial-NoDerivs License
Persistent DSpace Link
DOI of Published Version
https://doi.org/10.1016/J.JCP.2015.08.013
