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arXiv · 2412.03931

Near-ideal relaxed MHD in slab geometry

Arash Tavassoli·Stuart R. Hudson·Zhisong Qu·Matthew Hole
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Abstract

We investigate the solutions of the relaxed MHD model (RxMHD) of Dewar \& Qu [J. Plasma Phys. {\bf 88}, 835880101 (2022)]. This model generalizes Taylor relaxation by including the ideal Ohm's law constraint using an augmented Lagrangian method, providing a pathway to extend the multi-region relaxed MHD (MRxMHD) model. We present the first numerical solution of the RxMHD model by Dewar \& Qu, demonstrating that it is mathematically well-defined and computationally feasible for constructing MHD equilibria in slab geometry. We also show that a cross-field flow can exist without enforcing an arbitrary constraint on the angular momentum, as is done in the case of MRxMHD with flow. Our results also demonstrate the self-organization of fully relaxed regions during the optimization, which was an important motivation behind developing this model.

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Arash Tavassoli, Stuart R. Hudson, Zhisong Qu, Matthew Hole. 2024-12-05. Near-ideal relaxed MHD in slab geometry. https://doi.org/10.1063/5.0251817

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