波纹场和新经典撕裂模对托卡马克中快离子输运影响的数值模拟研究  

Numerical simulation of the effect of ripple and neoclassical tearing mode on tokamak particle transport

作　　者：刘锦 陈嘉盈 常悦悦 詹研 虞立敏 LIU Jin;CHEN Jiaying;CHANG Yueyue;ZHAN Yan;YU Limin(Department of Physics East China University of Science and Technology,Shanghai 200237,China)

机构地区：[1]华东理工大学理学院,上海200237

出　　处：《核技术》2021年第2期1-10,共10页Nuclear Techniques

基　　金：大学生创新创业训练计划项目(No.201910251085);国家自然科学基金项目(No.11875131)资助。

摘　　要：托卡马克是一种可能的受控核聚变实施方案,粒子输运在维持核聚变反应的进程中起着重要作用。使用导心运动代码ORBIT,针对波纹扰动和2/1新经典撕裂模(Neoclassical Tearing Mode,NTM)对圆截面托卡马克氘离子输运的影响开展了详细的数值模拟研究,同时计算了损失粒子的相空间分布。结果表明:粒子的损失随其初始位置和投射角(v///v)变化而改变,远离磁轴、接近最外层磁面的粒子损失率高;NTM主要造成通行粒子损失,波纹场主要造成捕获粒子损失,而同时具有这两种扰动情况下的粒子损失接近于其单独作用造成损失之和;波纹场会显著增加捕获粒子的环向角动量扩散而不影响通行粒子,NTM主要对通行粒子的环向角动量扩散有影响。粒子损失基本不受NTM频率改变而变化,而其环向角动量扩散则随NTM频率变化而变化。[Background]Tokamak is a possible implementation of controlled nuclear fusion whilst the particle transportation plays an important role in maintaining the progress of nuclear fusion reactions.[Purpose]This study aims to investigate the effects of ripple field and neoclassical tearing mode(NTM)on the migration of deuterium ions in Tokamak by numerical simulation.and provide a reference for the confinement of high energy particles.[Methods]The guiding center orbit code ORBIT was employed for numerical simulation.Effects of NTM and ripple field on particles with different positions,pitch angles and energies,were studied in details.[Results&Conclusions]Simulation results show that the particle loss rate is high under the condition of high magnetic surface and low pitch angle.NTM mainly causes the loss of passing particles,while the loss of trapped particles is mainly caused by ripple field.When both perturbations are considered,the loss of particles is approximately the sum of losses by two perturbations acting alone.Ripple field will significantly increase toroidal angular momentum diffusion of trapped particles without affecting the passing particles,whilst NTM mainly influences toroidal angular momentum diffusion of passing particles.The particle loss situation basically keeps the original characteristics regardless of NTM frequency varition,while the momentum diffusion condition of particle loss changes with the increase of NTM frequency.

关 键 词：波纹 新经典撕裂模 ORBIT 数值模拟 

分 类 号：TL62[核科学技术—核技术及应用]