Experimental and modeling researches of dust particles in the HL-2A tokamak

• 作者: HL-2A Team 严龙文 冨田幸博 冯震 杨青巍 段旭如 洪文玉 潘宇东 程钧 黄治辉
• 来源期刊: 中国物理B（英文版）
• 关键词: dust particles dust particle characteristics fast framing camera dust dynamics
• 年，卷（期）: 2015,（2）
• 页码范围: 025204-1-025204-7
• 页数: 1页
• 语种: 英文
• DOI: 10.1088/1674-1056/24/2/025204

摘要

The investigation of dust particle characteristics in fusion devices has become more and more imperative. In the HL-2A tokamak, the morphologies and compositions of dust particles are analyzed by using a scanning electron microscopy (SEM) and an energy dispersive x-ray spectroscopy (EDX) with mapping. The results indicate that the sizes of dust particles are in a range from 1 μm to 1 mm. Surprisingly, the stainless steel spheres with a diameter of 2.5 μm–30 μm are obtained. Production mechanism of the dust particles includes flaking, disintegration, agglomeration, and arcing. In addition, dynamic characteristics of the flaking dust particles are observed by a CMOS fast framing camera and simulated by a computer program. Both of the results display that the ion friction force is dominant in the toroidal direction, while the centrifugal force is crucial in the radial direction. Therefore, the visible dust particles are accelerated toriodally by the ion friction force and migrated radially by the centrifugal force. The averaged velocity of the grain is on the order of～100 m/s. These results provide an additional supplement for one of critical plasma-wall interaction (PWI) issues in the framework of International Thermonuclear Experimental Reactor (ITER) programme.