CAJ | 학술논문

采用数值模拟方法对托卡马克等离子体破裂期间的逃逸电子(RE)演化行为进行研究。程序所使用的物理模型包含了初级和次级两种RE产生机制，并耦合了麦克斯韦方程组。模拟结果显示：在等离子体破裂开始0.1~0.2ms后感应产生了很强的环向电场，持续约0.1ms之后该环向电场达到最大值，但是在大致2.5ms内逐渐衰减。同时模拟结果也证明了RE产生于等离子体中心处的局部区域，并且在破裂之后约1ms时间内就形成了RE束，实验中等离子体破裂之后出现的几十毫秒的电流平台主要是由RE携带的。从理论模拟与实验的对比中可以得出：HL-2A 15335次放电等离子体破裂期间欧姆电流转化为逃逸电流(RC)的转化率在40%~60%。次级产生机制在RE束的形成过程当中起到了关键作用。
채용수치모의방법대탁잡마극등리자체파렬기간적도일전자(RE)연화행위진행연구。정서소사용적물리모형포함료초급화차급량충RE산생궤제，병우합료맥극사위방정조。모의결과현시：재등리자체파렬개시0.1~0.2ms후감응산생료흔강적배향전장，지속약0.1ms지후해배향전장체도최대치，단시재대치2.5ms내축점쇠감。동시모의결과야증명료RE산생우등리자체중심처적국부구역，병차재파렬지후약1ms시간내취형성료RE속，실험중등리자체파렬지후출현적궤십호초적전류평태주요시유RE휴대적。종이론모의여실험적대비중가이득출：HL-2A 15335차방전등리자체파렬기간구모전류전화위도일전류(RC)적전화솔재40%~60%。차급산생궤제재RE속적형성과정당중기도료관건작용。
The simulation of runaway electron (RE) and electric field evolution during HL-2A disruption is presented using a self-consistent model, which is constituted by Maxwell’s equations and generation rate equation. The generation rate equation includes Dreicer and avalanche generation mechanisms of REs. The simulation shows that the electric field increases rapidly from 0.1~0.2ms after the disruption, reaches the maximum about 0.1 ms later, and lasts about 2.5ms. The simulation results also show that REs are produced mostly in the region around the magnetic axis and a RE beam forms at 1ms after disruption, tens of milliseconds steady-state current appearing after disruption is carried mainly by REs. Further, comparing between the simulation and the experimental results, it is found that 40%~60% of the Ohmic current is converted into runaway current (RC) during the disruption (discharge No. 15335) in HL-2A. Although the avalanche generation rate of REs is weaker than Dreicer generation mechanism in HL-2A, it plays a key role because of its larger action time than Dreicer generation mechanism.