小磁岛转动引起的沿磁力线电流对撕裂模的影响

摘要

利用离子香蕉轨道中心坐标和香蕉轨道平均算符,讨论了磁岛转动引起的沿磁力线电流分布及其对新经典撕裂模演进的影响.结果显示,考虑此电流的影响,当磁岛旋转频率ω=ω*i时,被离子香蕉轨道宽度效应削弱的自举电流驱动项基本恢复;当ω=ω*e时,离子香蕉轨道宽度效应对自举电流驱动项的削弱则加剧.这意味着磁岛转动方向不同时,此沿力线电流能显著增大或减弱离子香蕉轨道宽度效应对自举电流驱动项的削弱作用.%The parallel current distribution caused by magnetic island rotation and its influence on the neoclassical tearing modes(NTMs) evolution are investigated analytically by using ion banana orbit central coordinate and average operator. The results show that if this perturbed current is considered and island rotation frequency ω=ω*i, the bootstrap current term in NTMs evolution equation weakened by ion-banana-orbit-width (FBW) effect mostly recovers; while ω=ω*e, the bootstrap current term can be reduced dramatically by the effect. This means that the perturbed current caused by magnetic island rotation can enlarge or weaken the FBW weakening effect on bootstrap current driven term when magnetic island rotation direction is different.