Speaker
Dr
Yipo Zhang
(Southwestern Institute of Physics)
Description
Effect of the pedestal deposited impurity on the edge-localized mode (ELM) behaviour has been observed and intensively investigated in the HL-2A tokamak. Impurities have been externally seeded by a newly developed laser blow-off (LBO) system. Both mitigation and suppression of ELMs have been realized by LBO-seeded impurity. Measurements have shown that the LBO-seeded impurity particles are mainly deposited in the pedestal region. During the ELM mitigation phase, the pedestal density fluctuation is significantly increased, indicating that the ELM mitigation may be achieved by the enhancement of the pedestal transport. The transition from ELM mitigation to ELM suppression was triggered when the number of the LBO-seeded impurity exceeds a threshold value. During the ELM suppression phase, a harmonic coherent mode (HCM) is excited by the LBO-seeded impurity, and the pedestal density fluctuation is significantly decreased, the electron density is continuously increased, implying that HCM may reduce the pedestal turbulence, suppress ELMs, increase the pedestal pressure, thus extending the Peeling-Ballooning instability limit. It has been found that the occurance of the ELM mitigation and ELM suppression closely depends on the LBO laser spot diameter.
Country or International Organization | China, People's Republic of |
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Paper Number | EX/P5-8 |
Primary author
Dr
Yipo Zhang
(Southwestern Institute of Physics)
Co-authors
Dr
Annika Ekedahl
(CEA, IRFM)
Dr
Chunfeng Dong
(Southwestern Institute of Physics)
Dr
Deliang Yu
(Southwestern Institute of Physics)
Dr
Didier Mazon
(CEA Cadarache)
Dr
Gerardo Giruzzi
(IRFM, CEA)
Dr
Guoliang Xiao
(Southwestern Institute of Physics)
Dr
Guoliang Yuan
(Southwestern Institute of Physics)
Prof.
Jiaqi Dong
(Southwestern Institute of Physics)
Dr
Jinming Gao
(Southwestern Institute of Physics)
Mr
Jun Cheng
(Southwestern Institute of Physics)
Dr
Kai Zhang
(Southwestern Institute of Physics)
Dr
Lena DELPECH
(CEA, IRFM)
Min Jiang
(Southwestern Institute of Physics)
Dr
Min Xu
(Southwestern Institute of Physics)
Dr
Mitsutaka Isobe
(National Institute for Fusion Science (NIFS))
Dr
Pengfei Zhang
(Southwestern Institute of Physics)
Dr
Ping Sun
(Southwestern Institute of Physics)
Dr
Qingwei Yang
(Southwestern Institute of Physics)
Dr
Shaodong Song
(Southwestern Institute of Physics)
Dr
Tuong Hoang
(CEA - Institute for Magnetic Fusion Research)
Dr
Wei Chen
(Southwestern Institute of Physics)
Dr
Wulyu Zhong
(CnSWIP)
Prof.
Xianming SONG
(Southwestern Institute of Physics)
Mr
Xianying Song
(Southwestern Institute of Physics)
Dr
Xiaoquan Ji
(Southwestern Institute of Physics)
Dr
Xingyu Bai
(Southwestern Institute of Physics)
Mrs
Xu Li
(Southwestern Institute of Physics)
Prof.
Xuantong Ding
(Southwestern Institute of Physics)
Prof.
Xuru Duan
(Southwestern Institute of Physics)
Dr
Yan Zhou
(Southwestern Institute of Physics)
Prof.
Yi Liu
(southwestern institute of physics)
Dr
Yong Liu
(Southwestern Institute of Physics)
Dr
Yonggao Li
(Southwestern Institute of Physics)
Dr
Yves Peysson
(CEA)
Dr
Zhengying Cui
(Southwestern Institute of Physics)
Dr
Zhongbing Shi
(Southwestern Institute of Physics)
Dr
xiaolan zou
(CEA)