The role of MHD in causing impurity peaking in JET hybrid plasmas
The role of MHD in causing impurity peaking in JET hybrid plasmas
复制标题
DOI：
10.1088/0029-5515/56/6/066002
复制
发表时间：
2015-10
期刊：
影响因子：
3.3
通讯作者：
T. Hender;P. Buratti;F. Casson;B. Alper;Y. Baranov;M. Baruzzo;C. Challis;F. Koechl;K. Lawson-K.
中科院分区：
文献类型：
--
作者：
T. Hender;P. Buratti;F. Casson;B. Alper;Y. Baranov;M. Baruzzo;C. Challis;F. Koechl;K. Lawson-K.
在具有ITER-like壁面的JET （JET- ilw）中，混合等离子体运行发现，n > - 1撕裂活性可以显著提高高z杂质的轴上峰速率，从而显著降低放电性能。堆芯n = 1的不稳定性有利于去除等离子体堆芯中的杂质（如锯齿状或鱼骨状），但反过来也会降低堆芯的约束（特别是同时具有n = 3活性的情况下）。统计地考察了射流混合放电的磁流体动力不稳定性的性质，包括其先前的碳壁和随后的射流- ilw。提出了n bbb101岛如何增强轴上杂质输运积累过程的可能的定性模型。
In hybrid plasma operation in JET with its ITER-like wall (JET-ILW) it is found that n > 1 tearing activity can significantly enhance the rate of on-axis peaking of high-Z impurities, which in turn significantly degrades discharge performance. Core n = 1 instabilities can be beneficial in removing impurities from the plasma core (e.g. sawteeth or fishbones), but can conversely also degrade core confinement (particularly in combination with simultaneous n = 3 activity). The nature of magnetohydrodynamic instabilities in JET hybrid discharges, with both its previous carbon wall and subsequent JET-ILW, is surveyed statistically and the character of the instabilities is examined. Possible qualitative models for how the n > 1 islands can enhance the on-axis impurity transport accumulation processes are presented.