反常电子粘滞性引起的双撕裂模非线性演化

Nonlinear Evolution of Double Tearing Mode Mediated by Parallel Electron Viscosity

[目的]在常规电阻撕裂模方程的基础上加入反常电子粘滞性,用圆柱位形的磁流体动力学,对由反常电子粘滞性引起的双撕裂模的非线性发展做了数值研究。[方法]通过对非线性发展阶段磁岛和磁力线的演化分析,详细研究了两个有理面间距分别为较大、中等、较小3种情况下,由反常电子粘滞性引起的双撕裂模非线性发展的不同阶段的磁场拓扑结构的变化以及相关动力学特征,探讨了非线性发展的驱动问题。[结果]研究表明,两个有理面的间距的大小,对双撕裂模非线性发展有很大影响。间距中等时,会发生快速磁重联,对位形破坏最快最大。[结论]研究结果对托卡马克的位形设计和运行时的控制提供了参考。

[Introduction]By adding parallel electron viscosity into the normal equation of resistance tearing mode,the nonlinear behavior of double tearing mode(DTM)mediated by parallel electron viscosity is numerically investigated considering the magnetohydrodynamics in a periodic cylinder.[Method]The evolution of magnetic islands and magnetic flux during the nonlinear behavior stage of double tearing mode mediated by parallel electron viscosity were analyzed,to study the changes of the magnetic field topology in different phases and associated kinetic characteristics for different distances between the two resonant rational flux surfaces.In addition,the nonlinear driving for each case was discussed.[Result]The results show that the distance between the two resonant rational flux surfaces has a significant impact on the nonlinear behavior of double tearing mode.Rapid magnetic reconnection would occur at an intermediate distance,resulting in the fastest and most severe damage to the configuration.[Conclusion]The results of this study provide a reference for the configuration design and operational control of tokamaks.