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DOE OSTI · 2998245

Derivation and verification of the direct-sampling method for simulating Monte Carlo flight paths in tetrahedral meshes with linear finite-element cross sections

Vaquer, Pablo Andres [Los Alamos National Laboratory (LANL), Los Alamos, NM (United States)] (ORCID:0009000326088047)·Rising, Michael Evan [Los Alamos National Laboratory (LANL), Los Alamos, NM (United States)] (ORCID:0000000287122427)·Kulesza, Joel A. [Los Alamos National Laboratory (LANL), Los Alamos, NM (United States)] (ORCID:0000000226696339)·Weaver, Colin Andrew [Los Alamos National Laboratory (LANL), Los Alamos, NM (United States)] (ORCID:0000000263334185)
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Abstract

This paper provides a derivation of a direct-sampling approach for modeling continuously varying cross sections in tetrahedral-mesh-based Monte Carlo codes. Specifically, cross sections are spatially approximated using linear nodal finite elements. A linearization strategy is provided for non-linearly varying cross sections. The method is verified against seven analytical pure-absorber test problems. These test problems also highlight the benefit of using linear finite elements over element-wise-constant cross sections.

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70 PLASMA PHYSICS AND FUSION TECHNOLOGY97 MATHEMATICS AND COMPUTINGMonte Carlobarycentriccontinuously varyingcross sectiondirect samplingfinite elementmeshtetrahedralunstructured mesh

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Vaquer, Pablo Andres [Los Alamos National Laboratory (LANL), Los Alamos, NM (United States)] (ORCID:0009000326088047), Rising, Michael Evan [Los Alamos National Laboratory (LANL), Los Alamos, NM (United States)] (ORCID:0000000287122427), Kulesza, Joel A. [Los Alamos National Laboratory (LANL), Los Alamos, NM (United States)] (ORCID:0000000226696339), Weaver, Colin Andrew [Los Alamos National Laboratory (LANL), Los Alamos, NM (United States)] (ORCID:0000000263334185). 2025-09-30. Derivation and verification of the direct-sampling method for simulating Monte Carlo flight paths in tetrahedral meshes with linear finite-element cross sections. https://doi.org/10.1051/epjn%2F2025051

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