Stability analysis of ELMs in long-pulse discharges with ELITE code on EAST tokamak

作者：Yifeng Wang, Guosheng Xu, Baonian Wan, Guoqiang Li, N. Yan, Y. L. Li, Huiqian Wang, Y.K.M. Peng, Tianyang Xia, S. Ding, Ruihuan Chen, Qingquan Yang, Haiqing Liu, Qing Zang, Tao Zhang, Bo Lyu, J.C. Xu, Wei Feng, Liang Wang, Y J Chen, Zhengping Luo, G.H. Hu, Wei Zhang, L.M. Shao, Yunguan Ye, H. Lan, Liang Chen, Jie Li, N. Zhao, Qi Wang, P.B. Snyder, Y. Liang, J.P. Qian, Xianzu Gong, EAST team · 发表于：Plasma Physics and Controlled Fusion · 年份：2018 · DOI：10.1088/1361-6587/aab174 · 被引用次数：10 · 研究领域：Magnetic confinement fusion research、Fusion materials and technologies、Particle accelerators and beam dynamics

Abstract One challenge in long-pulse and high performance tokamak operation is to control the edge localized modes (ELMs) to reduce the transient heat load on plasma facing components. Minute-scale discharges in H-mode have been achieved repeatedly on Experimental Advanced Superconducting Tokamak (EAST) since the 2016 campaign and understanding the characteristics of the ELMs in these discharges can be helpful for effective ELM control in long-pulse discharges. The kinetic profile diagnostics recently developed on EAST make it possible to perform the pedestal stability analysis quantitatively. Pedestal stability calculation of a typical long-pulse discharge with ELITE code is presented. The ideal linear stability results show that the ELM is dominated by toroidal mode number n around 10–15 and the most unstable mode structure is mainly localized in the steep pressure gradient region, which is consistent with experimental results. Compared with a typical type-I ELM discharge with larger total plasma current ( I p = 600 kA), pedestal in the long-pulse H-mode discharge ( I p = 450 kA) is more stable in peeling-ballooning instability and its critical peak pressure gradient is evaluated to be 65% of the former. Two important features of EAST tokamak in the long-pulse discharge are presented by comparison with other tokamaks, including a wider pedestal correlated with the poloidal pedestal beta and a smaller inverse aspect ratio and their effects on the pedestal stability are discu...