Observation of High Recycling Steady H-mode edge and compatibility with improved core confinement mode on JFT-2M
Observation of High Recycling Steady H-mode edge and compatibility with improved core confinement mode on JFT-2M
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DOI：
10.1088/0029-5515/43/10/024
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发表时间：
2003-10
期刊：
影响因子：
3.3
通讯作者：
K. Kamiya;H. Kimura;H. Ogawa;H. Kawashima;K. Tsuzuki;M. Sato;Y. Miura
中科院分区：
文献类型：
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作者：
K. Kamiya;H. Kimura;H. Ogawa;H. Kawashima;K. Tsuzuki;M. Sato;Y. Miura
JFT-2M 在渗硼第一壁条件下发现了一种新的运行机制，可产生高循环稳定 (HRS) H 模式，其特点是在格林沃尔德密度 (ne/nGW) 70% 左右的高密度下具有良好的能量限制 (H89P ~ 1.6)、低辐射功率分数以及大型 ELM 的完全消失。伴随着 HRS H 模式转变，在血管壁处的磁探针上可以看到相干磁波动。这些相干波动的频率约为 10-100 kHz，且变化显着。它们被认为对于增强粒子传输非常重要，其特性类似于 Alcator C-Mod 报告的增强型 Dα (EDA) H 模式体系。之前在 JFT-2M 上观察到的 H' 模式在相干密度涨落方面与 EDA 模式具有共同特征，但它的出现是短暂的。 HRS 工作状态也与 EDA 模式类似，不同之处在于，即使在低 q95 (2 < q95 ≤ 3) 下也会出现 HRS。 HRS H 模式边缘条件的最重要特征是与高密度下改进的核心限制模式兼容，无需大型 ELM。我们已经证明，在 HRS H 模式边缘条件下可以产生内部传输势垒，在 ne/nGW ~ 70% 时瞬时实现 βNH89P ~ 6.2。
A new operational regime has been discovered on JFT-2M under the boronized first wall condition to produce the High Recycling Steady (HRS) H-mode, which is characterized by good energy confinement (H89P ~ 1.6) at a high density of around 70% of the Greenwald density (ne/nGW), low radiated power fraction, and complete disappearance of large ELMs. Accompanying the HRS H-mode transition, coherent magnetic fluctuation is seen on magnetic probes at the vessel wall. These coherent fluctuations have a frequency of the order of 10–100 kHz with significant variation. They are recognized as important in enhancing particle transport, whose characteristics are similar to the Enhanced Dα (EDA) H-mode regime reported from Alcator C-Mod. The H'-mode, previously observed on JFT-2M, had features in common with the EDA mode in terms of the coherent density fluctuation, but it appeared transiently. The HRS operating regime is also similar to the EDA mode, except that HRS is seen even at low q95 (2 < q95 ≤ 3). The most important feature of the HRS H-mode edge condition is compatibility with an improved core confinement mode at a high density without large ELMs. We have demonstrated that an internal transport barrier can be produced under a HRS H-mode edge condition, achieving βNH89P ~ 6.2 at ne/nGW ~ 70%, transiently.