Study on Impurity and Hydrogen Recycling Control Using Divertor-Plasma Simulator

(1)（2）实验研究了氢滞留对石墨板二次电子发射的增强作用，并与粒子模拟结果进行了比较。(3)利用偏滤器-等离子体模拟器NAGDIS-I对一种新的偏滤器概念--发射偏滤器板进行了实验研究，研究了其分岔现象的动力学行为，并与理论结果进行了比较。(4)用快速CCD相机观测了脉冲靶偏置产生的Ti Ⅰ和Ti Ⅱ可见光发射的二维分布，并将其沿磁场方向的分布沿着与Monte Calro模拟结果进行了比较。从这些比较中，杂质从靶的平行迁移被认为是由与体等离子体的摩擦力主导的。(5)研制了一套紧凑、快速的等离子体可见光和红外光发射CT系统，并获得了对H α、He Ⅰ和He Ⅱ发射的初步观测结果。(6)用B2程序研究了NAGDIS-1中的波加热特性，估算了不同等离子体条件下的加热效率。除上述研究活动外，还举行了两次研讨会，详细讨论了使用偏滤器-等离子体模拟器的合作研究。

(1) We have demonstrated the effectiveness of the metal-carbide overlaid graphite for erosion by high heat flux plasma(2) An enhancement of the secondary electron emission from the graphite plate by the hydrogen retention is investigated experimentally and compared with the particle simulation results.(3) An emissive divertor plate, as a new divertor concept, has been tested using the divertor-plasma simulator NAGDIS-I and the dynamic behavior of the bifurcation phenomena has been studied and compared with the theoretical one.(4) Two dimensional profiles of visible light emission of TiI and TiII generated by the pulse target biasing were observed by the fast CCD camera and its profile along the magnetic field was comapred with the results obtained by the Monte Calro simulation. From these comparison the parallel transort of the impurity from the target is considered to be dominated by the friction force with the bulk plasma.(5) Compact and fast CT system for the observation of visible and infrared light emission from plasmas has been developed and the preliminary results of observation of Halpha, HeI and HeII emission was obtained.(6) Characterstics of the wave heating in NAGDIS-I has been studied using B2 code and the heating efficiency was estimated for different plasma conditions.In addition to the research activities mentioned above, two workshops were held and the co-operative research using the divertor-plasma simulator was discussed in detail.