Assessment of the Lagrange Discrete Ordinates Equations for Three-Dimensional Neutron Transport

Journal Article · 02 August 2018 · Nuclear Science and Engineering

DOI: https://doi.org/10.1080/00295639.2018.1509569 · OSTI ID:1544721

Rowland, Kelly L.  ^[1]; Ahrens, Cory D. ^[2]; Hamilton, Steven ^[3]; Slaybaugh, R. N. ^[1]

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1. Univ. of California, Berkeley, CA (United States)
2. Los Alamos National Lab. (LANL), Los Alamos, NM (United States)
3. Oak Ridge National Lab. (ORNL), Oak Ridge, TN (United States)

The Lagrange Discrete Ordinates (LDO) equations, developed by Ahrens as an alternative to the traditional discrete ordinates formulation, have been implemented in Denovo, a threedimensional radiation transport code developed by Oak Ridge National Laboratory. The LDO equations retain the formal structure of the classical discrete ordinates equations but treat particle scattering in a different way. Solutions of the LDO equations have an interpolatory structure such that the angular flux can be naturally evaluated at directions other than the discrete ordinates used in arriving at the solutions, and the ordinates themselves may be chosen in a strategic way for the problem under consideration. Of particular interest is that the LDO equations have been shown to mitigate ray effects at increased angular resolutions. In this paper we present scalar flux solutions of the LDO equations for a small number of test cases of interest and compare the results against flux solutions generated using standard quadrature types. The LDO equations’ flux solutions were found to be comparable to those resultant from the standard quadrature types in value; results from the LDO equations were also found to be commensurate with those of standard quadrature types when comparing the flux solutions in the context of the experimental benchmark test case examined.

• Research Organization: Los Alamos National Lab. (LANL), Los Alamos, NM (United States)
• Sponsoring Organization: USDOE Office of Science (SC)
• Grant/Contract Number: 89233218CNA000001
• OSTI ID: 1544721
• Report Number(s): LA-UR--18-27192
• Journal Information: Nuclear Science and Engineering, Journal Name: Nuclear Science and Engineering Journal Issue: 3 Vol. 193; ISSN 0029-5639
• Publisher: American Nuclear Society - Taylor & FrancisCopyright Statement
• Country of Publication: United States
• Language: English