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arXiv · 2412.18922

Numerical solutions of resistive finite-pressure magnetohydrodynamic equilibria for non-axisymmetric toroidal plasmas

Jian Zhang·Ping Zhu·Chris C. Hegna
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Abstract

A hybrid spectral/finite-element code is developed to numerically solve the resistive finite-pressure magnetohydrodynamic equilibria without the necessity of postulating nested magnetic flux surfaces in the non-axisymmetric toroidal systems. The adopted approach integrates a hyperbolic parallel damping equation for pressure updating, along with a dynamic resistive relaxation for magnetic field. To address the nonaxisymmetry in toroidal geometry, a pseudo flux mapping is employed to relate the axisymmetric computational domain to the physical domain. On the computational mesh, an isoparametric C1-continuous triangular element is utilized to discretize the poloidal plane, which is complemented with a Fourier decomposition in the toroidal direction. The versatility of the code is demonstrated through its application to several different non-axisymmetric toroidal systems, including the inherently three-dimensional equilibria in stellarators, the helical-core equilibrium states in tokamak plasmas, and the quasi-single-helicity states in a reversed-field pinch.

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Jian Zhang, Ping Zhu, Chris C. Hegna. 2024-12-25. Numerical solutions of resistive finite-pressure magnetohydrodynamic equilibria for non-axisymmetric toroidal plasmas. https://arxiv.org/abs/2412.18922

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