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DOE OSTI · 23178670

Analysis of cell-based diffusion acceleration for the slice balance approach

Hackemack, M. W.
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Abstract

In this work, we perform analysis on the use of cell-based diffusion acceleration methodologies to accelerate the convergence of transport solutions discretized with the slice balance approach (SBA) on unstructured polygonal grids.We investigated both linear diffusion synthetic acceleration (DSA) and non linear diffusion acceleration (NDA), including its partial-current variant (pNDA). DSA and NDA were both shown to diverge for intermediate ranges of mesh optical thicknesses. However, pNDA and Krylov methods like GMRES and Broyden stabilized the acceleration schemes, including problems with degenerate cells formed by mesh refinement. (author)

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42 ENGINEERING46 INSTRUMENTATION RELATED TO NUCLEAR SCIENCE AND TECHNOLOGYBOLTZMANN EQUATIONCONVERGENCEITERATIVE METHODSMESH GENERATIONOPTIMIZATION

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BibTeXRIS

Hackemack, M. W.. 2022-07-01. Analysis of cell-based diffusion acceleration for the slice balance approach. https://www.osti.gov/biblio/23178670

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