Multiscale numerical methods for isothermal fluid models of confined plasmas

Chang Yang; Fabrice Deluzet

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arXiv · 2502.19436

Multiscale numerical methods for isothermal fluid models of confined plasmas

Chang Yang·Fabrice Deluzet

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Abstract

The aim of this work is to introduce a numerical method to cope with the multiscale nature of confined plasma physics. These investigations are focused on fluid plasma description under large magnetic field. The difficulties in this context stem from intense magnetization of the plasma, inducing a severe anisotropy, possible quasi-neutrality breakdowns, which may occur locally in the plasma and, eventually, the drift regime which prevails for the description of the electrons. These characteristics bring small parameters compared to the scale of the studied device. This work is therefore devoted to highlighting the difficulties specific to this context and to developing numerical methods efficient to cope with this multiscale nature of the physics within the framework of asymptotic-preserving methods.

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Chang Yang, Fabrice Deluzet. 2025-02-18. Multiscale numerical methods for isothermal fluid models of confined plasmas. https://arxiv.org/abs/2502.19436

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