Nuclear Engineering and Technology

Korean Nuclear Society (한국원자력학회)
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Experimental investigation on effect of ion cyclotron resonance heating on density fluctuation in SOL at EAST

  • Li, Y.C. (Advanced Energy Research Center, Shenzhen University) ;
  • Li, M.H. (Institute of Plasma Physics, Chinese Academy of Sciences) ;
  • Wang, M. (Institute of Plasma Physics, Chinese Academy of Sciences) ;
  • Liu, L. (Institute of Plasma Physics, Chinese Academy of Sciences) ;
  • Zhang, X.J. (Institute of Plasma Physics, Chinese Academy of Sciences) ;
  • Qin, C.M. (Institute of Plasma Physics, Chinese Academy of Sciences) ;
  • Wang, Y.F. (Institute of Plasma Physics, Chinese Academy of Sciences) ;
  • Wu, C.B. (Institute of Plasma Physics, Chinese Academy of Sciences) ;
  • Liu, L.N. (Advanced Energy Research Center, Shenzhen University) ;
  • Xu, J.C. (Institute of Plasma Physics, Chinese Academy of Sciences) ;
  • Ding, B.J. (Institute of Plasma Physics, Chinese Academy of Sciences) ;
  • Lin, X.D. (Advanced Energy Research Center, Shenzhen University) ;
  • Shan, J.F. (Institute of Plasma Physics, Chinese Academy of Sciences) ;
  • Liu, F.K. (Institute of Plasma Physics, Chinese Academy of Sciences) ;
  • Zhao, Y.P. (Institute of Plasma Physics, Chinese Academy of Sciences) ;
  • Zhang, T. (Institute of Plasma Physics, Chinese Academy of Sciences) ;
  • Gao, X. (Advanced Energy Research Center, Shenzhen University)
  • Received : 2021.04.07
  • Accepted : 2021.07.18
  • Published : 2022.01.25
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Abstract

The suppression of high-intensity blob structures in the scrape-off layer (SOL) by ion-cyclotron range of frequencies (ICRF) power, leading to a decrease in the turbulent fluctuation level, is observed first in the Experimental Advanced Superconducting Tokamak (EAST) experiment. This suppression effect from ICRF power injection is global in the whole SOL at EAST, i.e. blob structures both in the regions that are magnetically connected to the active ICRF launcher and in the regions that are not connected to the active ICRF launcher could be suppressed by ICRF power. However, more ICRF power is required to reach the full blob structure suppression effect in the regions that are magnetically unconnected to the active launcher than in the regions that are magnetically connected to the active launcher. Studies show that a possible reason for the blob suppression could be the enhanced Er × B shear flow in the SOL, which is supported by the shaper radial gradient in the floating potential profiles sensed by the divertor probe arrays with increasing ICRF power. The local RF wave power unabsorbed by the core plasma is responsible for the modification of potential profiles in the SOL regions.

Keywords

Acknowledgement

This work was supported by the National Key Research and Development Program of China (Grant No. 2016YFA0400603, 2016YFA0400602), the National Natural Science Foundation of China (Grant No. 11975266, 11675214, 11775259, 11805233, U19A20113), and Shenzhen Clean Energy Research Institute.

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