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DOE OSTI · 2515689

Diffusion Limit–Preserving Lumped DFEMs on AMR Meshes

Till, A. [Lawrence Livermore National Laboratory (LLNL), Livermore, CA (United States)] (ORCID:0000000290635629)
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Abstract

Here, we present sweep-compatible, novel upwinding recipes for the bilinear discontinuous (BLD) finite element method (FEM) that allows lumped BLD to be used on adaptive mesh refinement (AMR) meshes for thick transport applications without adding additional degrees of freedom at hanging nodes that exist on refinement boundaries. We analyze the properties of the upwinding and lumping that are needed for BLD to get the thick diffusion limit on such meshes, present results demonstrating locking with the wrong recipe, and present results showing error convergence and robustness properties for two diffusive problems on a variety of AMR meshes.

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42 ENGINEERING73 NUCLEAR PHYSICS AND RADIATION PHYSICS97 MATHEMATICS AND COMPUTINGDiscontinuous finite element method (DFEM)Nuclear science and engineering, Mathematics and Computingadaptive mesh refinement (AMR)lumpedthick diffusion limit

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Till, A. [Lawrence Livermore National Laboratory (LLNL), Livermore, CA (United States)] (ORCID:0000000290635629). 2024-12-18. Diffusion Limit–Preserving Lumped DFEMs on AMR Meshes. https://doi.org/10.1080/00295639.2024.2400437

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