Study of negative triangularity configuration on HL-3 tokamak

doi:10.16568/j.0254-6086.202504011

Abstract

Abstract: The equilibrium code EFIT is used to research the negative triangularity(NT) plasma configuration with different elongation (κ) and negative triangularity (δ) in the HL-3 tokamak, and GATO code is employed to perform ideal magneto hydrodynamic (MHD) stability analysis of these configurations as well as the influence of κ and δ on equilibrium stability. The EFIT research results show that the equilibrium configurations of 1 MA plasma current can be realized with elongation κ from 1.4 to 1.8 and negative triangularity δ from -0.4 to -0.7 under present magnetic field coil conditions in the HL-3 tokamak. GATO is used to analyze the n=1 kink mode, which has a decisive influence on MHD instability in tokamak plasma. The analysis results exhibit that the plasma elongation and the triangularity significantly affect the MHD instability, and the larger the plasma elongation, the more stable the plasma equilibrium configuration. In contrast, the plasma equilibrium become more instabilities with increase of the absolute value |δ|.

Key words: HL-3 tokamak, Negative triangularity, Equilibrium configuration

摘要： 利用平衡程序 EFIT 开展了 HL-3 装置具有不同拉长比(κ)和反三角形变(δ)的等离子体位形的数值模拟研究，并用GATO 程序开展了这些平衡位形的理想磁流体(MHD)的稳定性分析以及 κ 和 δ 对平衡稳定性的影响。EFIT 的模拟结果显示：在HL-3 装置现有磁场线圈条件下可以实现拉长比(κ=1.4~1.8)和反三角形变[δ=(-0.4)~(-0.7)]的兆安(MA)量级等离子体电流的平衡位形。在 GATO 的 MHD 稳定性分析中，考虑的是 n=1 扭曲模，该模对托卡马克等离子体 MHD 不稳定性有决定性的影响。分析结果表明：等离子体拉长比和三角形变明显影响 MHD 不稳定性，等离子体拉长比越大，越有利于平衡位形的稳定，而负三角形变绝对值|δ|的分析结果相反，|δ|越大越不稳定。

关键词: HL-3 托卡马克, 反三角形变, 平衡位形

CLC Number:

TL62+4

LI Ze-meng, SUN Ai-ping, WANG Yuan-zhen, LI Zheng-ji, WANG Zhuo, LIU Yi. Study of negative triangularity configuration on HL-3 tokamak[J]. Nuclear Fusion and Plasma Physics, 2025, 45(4): 446-452.

李泽萌, 孙爱萍, 王元震, 李正吉, 王卓, 刘仪 . HL-3 装置反三角形变位形的研究[J]. 核聚变与等离子体物理, 2025, 45(4): 446-452.

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