Discretization form of the continuity condition at the polar axis, with application to the gyrokinetic simulation in a magnetic fusion torus

Tiannan Wu; Zihao Wang; Shaojie Wang

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arXiv · 2402.03657

Discretization form of the continuity condition at the polar axis, with application to the gyrokinetic simulation in a magnetic fusion torus

Tiannan Wu·Zihao Wang·Shaojie Wang

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Abstract

A new computational method to solve the hyperbolic (Vlasov) equation and the elliptic (Poisson-like) equation at the polar axis is proposed. It is shown that the value of a scalar function at the polar axis can be predicted by its neighbouring values based on the continuity condition. This continuity condition systematically solves the pole problems including the singular factor 1/r in the hyperbolic equation and the inner boundary in the elliptic equation. The proposed method is applied to the global gyrokinetic simulation of the tokamak plasma with the magnetic axis included.

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Tiannan Wu, Zihao Wang, Shaojie Wang. 2024-02-06. Discretization form of the continuity condition at the polar axis, with application to the gyrokinetic simulation in a magnetic fusion torus. https://arxiv.org/abs/2402.03657

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