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DOE OSTI · 2202597

Superior discretizations and AMG solvers for extremely anisotropic diffusion via hyperbolic operators [Slides]

Southworth, Benjamin Scott·Wimmer, Golo Albert·Tang, Xianzhu·Gregory, Thomas
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Abstract

Diffusion in magnetic confinement fusion is extremely anisotropic in the direction of field lines. Rewrote diffusion system based on directional gradients, apply discretization and solver techniques developed for advection. Orders of magnitude decrease in error and solve wallclock time vs. traditional methods. The next steps include: (1) incorporate into larger MHD simulations, (2) better solvers for closed field lines or mixed regimes, and (3) possibly other extremely anisotropic equations.

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97 MATHEMATICS AND COMPUTING

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Southworth, Benjamin Scott, Wimmer, Golo Albert, Tang, Xianzhu, Gregory, Thomas. 2023-10-17. Superior discretizations and AMG solvers for extremely anisotropic diffusion via hyperbolic operators [Slides]. https://doi.org/10.2172/2202597

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