论文标题
关于倾斜不稳定性的非线性粘附演化期间浆液链的生长速率
On the growth rate of plasmoid chains during nonlinear viscoresistive evolution of the tilt instability
论文作者
论文摘要
我们通过二维不可压缩的磁性水力动力学（MHD）数值模拟进行了研究，这是快速碰撞磁性重新连接状态的开始阶段，当lundquist数字S超过关键值时，该固定链链链的形成支持。本研究将以磁性prandtl数字PM = 1（Baty 2020）获得的先前结果扩展到一系列不同的PM值。我们使用FinMHD代码，其中采用一组减少的抗Visco MHD方程来形成两种准单词电流层，这是由于倾斜不稳定的结果。结果加强了这样一个结论，即在当前纸上在较慢的阿尔菲维时间尺度上，在当前纸上形成的先前静止阶段之后，获得了突然的超级阿尔抗生长阶段（当pm不太高）。我们将结果与浆液不稳定性的一般理论的预测进行了比较。我们还讨论了该发生阶段达到随后的随机时间依赖性重新连接制度的重要性，在这种重新连接方面，在该方案中，即可获得与S无关的快速时间平均速率。最后，我们简要讨论了结果的相关性，以解释太阳能电晕和Tokamaks内部破坏的爆发活动。
We investigate by means of two-dimensional incompressible magnetohydrodynamic (MHD) numerical simulations, the onset phase of the fast collisional magnetic reconnection regime that is supported by the formation of plasmoid chains when the Lundquist number S exceeds a critical value. The present study extends previous results obtained at magnetic Prandtl number Pm = 1 (Baty 2020) to a range of different Pm values. We use FINMHD code where a set of reduced visco-resistive MHD equations is employed to form two quasi-singular current layers as a consequence of the tilt instability. The results reinforce the conclusion that, a phase of sudden super-Alfvenic growth (when Pm is not too high) of plasmoid chains is obtained, following a previous quiescent phase during current sheet formation on a slower Alfvenic time scale. We compare our results with predictions from the general theory of the plasmoid instability. We also discuss the importance of this onset phase to reach the ensuing stochastic time-dependent reconnection regime, where a fast time-averaged rate independent of S is obtained. Finally, we briefly discuss the relevance of our results to explain the flaring activity in solar corona and internal disruptions in tokamaks.
