Enhanced particle transport events approaching the density limit of the J-TEXT tokamak
Enhanced particle transport events approaching the density limit of the J-TEXT tokamak
复制标题
DOI：
10.1088/1741-4326/ac36f2
复制
发表时间：
2021-11
期刊：
影响因子：
3.3
通讯作者：
T. Long;Patrick H Diamond;R. Ke;Lin Nie;Min Xu;Xiaoyi Zhang;Bingli Li;Zhipeng Chen;Xin Xu;Zhanhui Wang;Ting Wu;Wenjing Tian;Jinbang Yuan;B. Yuan;Shaobo Gong;Chenyu Xiao;Jinming Gao;Zhigang Hao;Nengchao Wang;Z. Chen;Zhoujun Yang;Li Gao;Yonghua Ding;Y. Pan;Wei Chen;G. Hao;Jiquan Li;Wulyu Zhong;Xuru Duan
中科院分区：
文献类型：
--
作者：
T. Long;Patrick H Diamond;R. Ke;Lin Nie;Min Xu;Xiaoyi Zhang;Bingli Li;Zhipeng Chen;Xin Xu;Zhanhui Wang;Ting Wu;Wenjing Tian;Jinbang Yuan;B. Yuan;Shaobo Gong;Chenyu Xiao;Jinming Gao;Zhigang Hao;Nengchao Wang;Z. Chen;Zhoujun Yang;Li Gao;Yonghua Ding;Y. Pan;Wei Chen;G. Hao;Jiquan Li;Wulyu Zhong;Xuru Duan
随着J-TEXT托卡马克密度极限的接近，发现并分析了增强粒子输运事件。观察到边缘剪切层崩溃和雷诺功率的比湍流产生减少。同时，湍流内能通量的发散（即湍流传播）增加，表明剪切层崩溃触发向外传播事件。相关性研究表明，增强的粒子输运事件是准相干的，主要表现在密度涨落上，具有正偏度。电子绝热性是传递事件开始的关键参数。当α < 0.35时，随着密度接近格林沃尔德密度，湍流扩散和密度涨落都迅速增加。两者合计，这些结果阐明了边缘剪切层，密度波动，粒子输运事件，湍流传播和等离子体边缘冷却的密度极限接近之间的联系。
Enhanced particle transport events are discovered and analyzed as the density limit of the J-TEXT tokamak is approached. Edge shear layer collapse is observed and the ratio of Reynolds power to turbulence production decreases. Simultaneously, the divergence of turbulence internal energy flux (i.e. turbulence spreading) increases, indicating that shear layer collapse triggers an outward spreading event. Studies of correlations show that the enhanced particle transport events are quasi-coherent, and manifested primarily in density fluctuations which exhibit positive skewness. Electron adiabaticity emerges as the critical parameter which signals transport event onset. For α < 0.35 as density approaches the Greenwald density, both turbulence spreading and density fluctuations rise rapidly. Taken together, these results elucidate the connections between edge shear layer, density fluctuations, particle transport events, turbulence spreading and plasma edge cooling as the density limit is approached.