HL-2A 装置上撕裂模与湍流相互作用研究的进展

doi:10.16568/j.0254-6086.202503012

摘要/Abstract

摘要：

开展等离子体中撕裂模与湍流之间的相互作用的研究，有助于理解撕裂模对等离子体输运的影响，对在大型聚变装置上发展撕裂模的有效控制技术及维持等离子体高约束性能具有重要指导意义。结合HL-2A 装置实验与数值模拟，系统研究了等离子体中撕裂模与湍流的多尺度相互作用机制及其对能量输运的影响。研究取得以下重要发现：(1) 发现撕裂模磁岛边界形成强极向流剪切层；(2) 证实了撕裂模旋转对湍流幅度的调制效应存在临界磁岛宽度阈值，为Fitzpatrick 理论提供了直接实验证据；(3) 创新性地发现湍流可通过非线性过程横越磁岛传播，揭示了大磁岛边界激发准相关模湍流的物理现象，并提出非局域相位耦合的湍流传播机制；(4) 阐明了磁岛X 点区域湍流诱发等离子体热淬灭的物理机理。这些结果表明，主动调控湍流可能成为控制撕裂模稳定性和缓解破裂的一种新方法。

关键词: 撕裂模, 磁岛, 湍流, 极向流, 湍流传播, 多尺度相互作用

Abstract:

Investigating the interaction between tearing modes and turbulence in plasmas is crucial for understanding the impact of tearing modes on plasma transport, which holds significant implications for developing effective control techniques for tearing modes and maintaining high-confinement plasma performance in large fusion devices. The multi-scale interaction mechanisms between tearing modes and turbulence, as well as their influence on energy transport were investigated systematically, through experiments on the HL-2A tokamak combined with numerical simulations. The key findings are as follows: (1) A strong poloidal flow shear layer is observed at the boundary of the tearing-mode magnetic island; (2) The modulation effect of tearing-mode rotation on turbulence amplitude is confirmed to exhibit a critical magnetic island width threshold, providing direct experimental evidence for Fitzpatrick’s theory; (3) For the first time, nonlinear cross-island turbulence spreading is discovered, revealing the physical phenomenon exciting quasi-coherent mode turbulence at large magnetic island boundaries, with a proposed non-local phase coupling mechanism underlying this phenomenon; (4) Thephysical mechanism, by which the turbulence near the X-point of magnetic islands triggers plasma thermal quench, is elucidated. These results suggest that active turbulence regulation may serve as a novel approach for controlling tearing mode stability and mitigating disruptions.

Key words: Tearing mode, Magnetic island, Turbulence, Poloidal flow, Turbulence spreading, Multi-scale interaction

中图分类号:

蒋敏, 许宇鸿, 钟武律, 陈伟, 石中兵, 李继全, 张毅, 栗钰彩. HL-2A 装置上撕裂模与湍流相互作用研究的进展[J]. 核聚变与等离子体物理, 2025, 45(3): 332-341.

JIANG Min, XU Yu-hong, ZHONG Wu-lü, CHEN Wei, SHI Zhong-bing, LI Ji-quan, ZHANG Yi, LI Yu-cai. Progress of investigation on the interaction between tearing mode and turbulence in HL-2A tokamak[J]. Nuclear Fusion and Plasma Physics, 2025, 45(3): 332-341.

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