Speaker
Nengchao Wang
Description
See the full Abstract at http://ocs.ciemat.es/EPS2018ABS/pdf/P4.1028.pdf
Preliminary research on the island divertor configuration by applying
3/1 RMP in J-TEXT
Nengchao Wang1, Y. Liang1, 2, 3, Xiaolong Zhang1, Jie Yang1, Qiming Hu4, Song Zhou1,
Zebao Song1, Da Li1, Zhuo Huang1, Linzi Liu1, Chengshuo Shen1, Bo Rao1, Y. H. Ding1 and
the J-TEXT team
1
International Joint Research Laboratory of Magnetic Confinement Fusion and Plasma
Physics, Huazhong University of Science and Technology, Wuhan, China
2
Forschungszentrum Jülich, Jülich, Germany
3
Institute of Plasma Physics, Chinese Academy of Sciences, Hefei, China
4
Princeton Plasma Physics Laboratory (PPPL), Princeton, USA
*E-mail: wangnc@hust.edu.cn
The island divertor configuration [1] was first proposed in 1977 for tokamak. It has been
established successfully in various tokamaks, e.g. TEXTOR, and stellarators [2], such as
W7-AS, LHD and recently in W7-X, leading to the impurity screening effect and the heat
flux reduction on the target.
In the recent campaign of J-TEXT tokamak, an experimental attempt have been made to
form an island divertor configuration. An edge 3/1 island has been excited by applying the
resonant magnetic perturbation (RMP) with dominate m/n = 3/1 component to a plasma with
edge safety factor qa >~ 3. The 2/1 component of external RMP fields was kept at a low level
to avoid exciting large 2/1 locked mode. Once the 3/1 island has been excited, the radial and
poloidal profiles of the floating potential, the intensity of CIII radiation, the edge toroidal
rotation varied significantly. The poloidal profiles of the floating potential measured at the
limiters, varied during the formation of 3/1 island, indicating the impact of the 3/1 island on
the footprints.
In addition, the preliminary design for building a set of island divertor coils utilizing 4/1
island will also be discussed.
[1] F. Karger and K. Lackner, Physcis letters A 61 (1977) 385
[2] R. König, et al., Plasma Phys. Control. Fusion 44 (2002) 2365
