Type II ELMy H modes on ASDEX Upgrade with good confinement at high density
Type II ELMy H modes on ASDEX Upgrade with good confinement at high density
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DOI：
10.1088/0029-5515/41/9/301
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发表时间：
2001-09
期刊：
影响因子：
3.3
通讯作者：
J. Stober;M. Maraschek;G. Conway;O. Gruber;A. Herrmann;A. Sips;W. Treutterer;H. Zohm
中科院分区：
文献类型：
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作者：
J. Stober;M. Maraschek;G. Conway;O. Gruber;A. Herrmann;A. Sips;W. Treutterer;H. Zohm
在ASDEX升级中观察到了具有良好约束的H模和具有II型或草状ELMs特征的小ELMs。这种ELM行为对于在任何下一步装置中最小化偏滤器瓦片的侵蚀是必不可少的。这是第一次，这种有利的ELM类型的操作可以证明接近格林沃尔德密度。即使对于这样高的密度，能量约束时间接近最近的H模式缩放。高密度甚至似乎是有利的，因为ASDEX升级上的稳态纯II型ELMy H模式相仅在e/GW ≥ 0.85以上获得。额外的要求是q95 ≥ 4.2，平衡态接近于平均三角度δ = 0.40的双零组态。对于这些小ELMs，观测到频率为1.30 kHz，主模数为环向3和4，极向≥ 14的磁性前兆。
H modes with good confinement and small ELMs with the characteristics of type II or grassy ELMs have been observed on ASDEX Upgrade. Such an ELM behaviour is essential to minimize erosion of the divertor tiles in any next step device. For the first time, operation with this favourable ELM type could be demonstrated close to the Greenwald density. Even for such high densities, energy confinement times were close to recent H mode scalings. High density even seems to be favourable, since steady state pure type II ELMy H mode phases on ASDEX Upgrade are obtained only above e/GW ≥ 0.85. Additional requirements are q95 ≥ 4.2 and an equilibrium close to a double null configuration with an average triangularity δ = 0.40. For these small ELMs magnetic precursors are observed with a frequency of ≈ 30 kHz and dominant mode numbers of toroidally 3 and 4 and poloidally ≥ 14.