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DOE OSTI · 1296672

A stable 1D multigroup high-order low-order method

Yee, Ben Chung·Wollaber, Allan Benton·Haut, Terry Scot·Park, HyeongKae
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Abstract

The high-order low-order (HOLO) method is a recently developed moment-based acceleration scheme for solving time-dependent thermal radiative transfer problems, and has been shown to exhibit orders of magnitude speedups over traditional time-stepping schemes. However, a linear stability analysis by Haut et al. (2015 Haut, T. S., Lowrie, R. B., Park, H., Rauenzahn, R. M., Wollaber, A. B. (2015). A linear stability analysis of the multigroup High-Order Low-Order (HOLO) method. In Proceedings of the Joint International Conference on Mathematics and Computation (M&C), Supercomputing in Nuclear Applications (SNA) and the Monte Carlo (MC) Method; Nashville, TN, April 19–23, 2015. American Nuclear Society.) revealed that the current formulation of the multigroup HOLO method was unstable in certain parameter regions. Since then, we have replaced the intensity-weighted opacity in the first angular moment equation of the low-order (LO) system with the Rosseland opacity. Furthermore, this results in a modified HOLO method (HOLO-R) that is significantly more stable.

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97 MATHEMATICS AND COMPUTINGthermal transfer, stability analysis, discontinuous Galerkin

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BibTeXRIS

Yee, Ben Chung, Wollaber, Allan Benton, Haut, Terry Scot, Park, HyeongKae. 2016-07-13. A stable 1D multigroup high-order low-order method. https://doi.org/10.1080/23324309.2016.1187172

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