Long-pulse high-performance H-mode plasmas achieved on EAST

作者：J. Huang, Xianzu Gong, A. M. Garofalo, J.P. Qian, Rui Ding, X. J. Zhang, Jiale Chen, Miaohui Li, Yaowei Yu, Yifeng Wang, Yao Huang, Hang Si, L.Y. Meng, Tianqi Jia, Yuxin Sun, Long Zeng, Le Han, Yanmin Duan, A. Ekedahl, C. T. Holcomb, R. Maingi, Erzhong Li, Haiqing Liu, Bo Lyu, Q. Ren, Youwen Sun, Liang Wang, Liqing Xu, Damao Yao, Qingquan Yang, Qing Zang, Bin Zhang, Ling Zhang, Xuemei Zhai, Guizhong Zuo, Guoqiang Li, Pengfei Zi, Mao Wang, Handong Xu, Qiping Yuan, Yahong Xie, Liansheng Huang, Jian Zhang, Ya‐Lin Hu, Weibin Xi, Zhiwei Zhou, Zhengchu Wang, Bin Guo, Guosheng Xu, Jiansheng Hu, Kun Lü, Yuntao Song, Baonian Wan, Jiangang Li, EAST team · 发表于：Physics of Plasmas · 年份：2023 · DOI：10.1063/5.0146690 · 被引用次数：19 · 研究领域：Magnetic confinement fusion research、Fusion materials and technologies、Particle accelerators and beam dynamics

A record duration of a 310 s H-mode plasma (H98y2 ∼ 1.3, ne/nGW ∼ 0.7, fBS > 50%) has been recently achieved on experimental advanced superconducting tokamak (EAST) with metal walls, exploiting the device's improved long-pulse capabilities. The experiment demonstrates good control of tungsten concentration, core/edge MHD stability, and particle and heat exhaust with an ITER-like tungsten divertor and zero injected torque, establishing a milestone on the path to steady-state long-pulse high-performance scenarios in support of ITER and CFETR. Important synergistic effects are leveraged toward this result, which relies purely on radio frequency (RF) powers for heating and current drive (H&CD). On-axis electron cyclotron heating enhances the H&CD efficiency from lower hybrid wave injection, increasing confinement quality and enabling fully non-inductive operation at high density (ne/nGW ∼ 70%) and high poloidal beta (βP ∼ 2.5). A small-amplitude grassy edge localized mode regime facilitates the RF power coupling to the H-mode edge and reduces divertor sputtering/erosion. The high energy confinement quality (H98y2 ∼ 1.3) is achieved with the experimental and simulated results pointing to the strong effect of Shafranov shift on turbulence. Transport analysis suggests that trapped electron modes dominate in the core region during the record discharge. The detailed physics processes (RF synergy, core-edge integration, confinement properties, etc.) of the steady-state o...