Experimental Investigation of Lower Hybrid Wave Coupling in HT-7  

作　　者：KONG Erhua DING Bojiang ZHANG Ting QIN Yongliang SHAN Jiafang LIU Fukun LI Miaohui ZHANG Lei WANG Mao LIU Liang XU Handong JIA Hua WU Zege FENG Jianqiang ZHAO Lianmin YANG Yong 

机构地区：[1]Institute of Plasma Physics, Chinese Academy of Sciences, Hefei 230031, China [2]School of Physics, Hefei University of Technology, Hefei 230009, China [3]High Magnetic Field Laboratory, Chinese Academy of Sciences, Hefei 230031, China

出　　处：《Plasma Science and Technology》2013年第10期989-995,共7页等离子体科学和技术（英文版）

基　　金：supported by National Natural Science Foundation of China （Nos. 10875149, 10928509, 10805057, and 10905069）, the National Magnetic Confinement Fusion Science Program of China （Nos. 2010GB105003, 2010GB105004）, and the Dean Foundation of the Hefei Institutes of Physical Science, Chinese Academy of Sciences

摘　　要：Experiments on lower hybrid wave （LHW） coupling were investigated in the HT- 7 tokamak. Good coupling of LHW plasma has been demonstrated at different conditions in the HT-7 tokamak. Relevant results have proved that LHW-plasma coupling is affected by the phase difference between adjacent waveguides. Furthermore, the edge density around the grill and relevant coupling can be adjusted by changing the plasma line average density or the gap value between the LH grill and the last closed flux surfaces （LCFS）. It is found that the coupling of LHWs becomes poor when the edge density around the LH grill is large enough in the HT-7 tokamak, and that coupling remains good with a proper edge density. With increasing LHW power, it is also found that the reflection coefficients （RCs） increase due to non-linear effects under conditions of low edge recycling, but can decrease under high edge recycling. The edge density depends mainly on the competition between the ponderomotive force （PMF） and the edge recycling intensity in the HT-7 tokamak.Experiments on lower hybrid wave （LHW） coupling were investigated in the HT- 7 tokamak. Good coupling of LHW plasma has been demonstrated at different conditions in the HT-7 tokamak. Relevant results have proved that LHW-plasma coupling is affected by the phase difference between adjacent waveguides. Furthermore, the edge density around the grill and relevant coupling can be adjusted by changing the plasma line average density or the gap value between the LH grill and the last closed flux surfaces （LCFS）. It is found that the coupling of LHWs becomes poor when the edge density around the LH grill is large enough in the HT-7 tokamak, and that coupling remains good with a proper edge density. With increasing LHW power, it is also found that the reflection coefficients （RCs） increase due to non-linear effects under conditions of low edge recycling, but can decrease under high edge recycling. The edge density depends mainly on the competition between the ponderomotive force （PMF） and the edge recycling intensity in the HT-7 tokamak.

关 键 词：LH wave coupling PLASMA edge density phase difference ponderomotiveforce 

分 类 号：TL631.24[核科学技术—核技术及应用] TN248.6