Achieving temporary divertor plasma detachment with MARFE events by pellet injection in the EAST superconducting tokamak

Guozhong DENG (邓国忠); Liang WANG (王亮); Xiaoju LIU (刘晓菊); Yanmin DUAN (段艳敏); Jiansheng HU (胡建生); Changzheng LI (李长征); Ling ZHANG (张凌); Shaocheng LIU (刘少承); Huiqian WANG (汪惠乾); Liang CHEN (陈良); Jichan XU (许吉禅); Wei FENG (冯威); Jianbin LIU (刘建斌); Huan LIU (刘欢); Guosheng XU (徐国盛); Houyang GUO (郭后扬); Xiang GAO (高翔); the EAST team

doi:10.1088/1009-0630/19/1/015101

Plasma Science and Technology > 2017 > 19(1): 15101-015101. > DOI: 10.1088/1009-0630/19/1/015101

Guozhong DENG (邓国忠), Liang WANG (王亮), Xiaoju LIU (刘晓菊), Yanmin DUAN (段艳敏), Jiansheng HU (胡建生), Changzheng LI (李长征), Ling ZHANG (张凌), Shaocheng LIU (刘少承), Huiqian WANG (汪惠乾), Liang CHEN (陈良), Jichan XU (许吉禅), Wei FENG (冯威), Jianbin LIU (刘建斌), Huan LIU (刘欢), Guosheng XU (徐国盛), Houyang GUO (郭后扬), Xiang GAO (高翔), the EAST team. Achieving temporary divertor plasma detachment with MARFE events by pellet injection in the EAST superconducting tokamak[J]. Plasma Science and Technology, 2017, 19(1): 15101-015101. DOI: 10.1088/1009-0630/19/1/015101

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Achieving temporary divertor plasma detachment with MARFE events by pellet injection in the EAST superconducting tokamak

1 Institute of Plasma Physics, Chinese Academy of Sciences, Hefei 230031, People’s Republic of China 2 University of Science and Technology of China, Hefei 230026, People’s Republic of China

Funds: This work was supported by National Natural Science Foundation of China (Nos. 11575236, 11275231, 11305206) and the National Magnetic Confinement Fusion Science Program of China (Nos. 2013GB107003, 2014GB106005, 2015GB101000).

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Received Date: March 23, 2016

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Abstract

Abstract

A new pellet injection system has been equipped on the experimental advanced superconducting tokamak (EAST) in the 2012 campaign, with a pellet size of Ø 2mm×2 mm, a frequency of 1Hz–10 Hz and velocity of 150 m s⁻¹ –300 m s⁻¹. The deuterium pellet is well-known for plasma fuelling as well as for triggering the edge localized mode (ELM). In the 2012 campaign, pellet injection experiments were successfully carried out on EAST. Temporary plasma detachment achieved by deuterium pellets has been observed in a double null (DN) divertor configuration, with multi-pellet injections at a repetition frequency of 2 Hz. The partial detachment of the outer divertors and complete detachment of the inner divertors was achieved after 35 ms of each pellet injection, which have a duration of 30–60 ms with the maximum degree of detachment (DOD) reaching 3.5 and 37, respectively. Meanwhile, the multifaceted asymmetric radiation from the edge (MARFE) phenomena was also observed at the high field side (HFS) near both the lower and upper X-points with radiation loss suddenly increased to about 15%–70%, which may be the main cause of divertor plasma detachment. The temporary detachment induced by pellet injection may act as a new way to study divertor detachment behaviors.
- divertor,
- MARFE,
- pellet injection

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References (18)

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