一种确定模拟的行星际MHD激波局地参数的新方法

简要阐述了分析模拟的行星际磁流体力学（MHD）激波的局部性质时，采用无厚度局部平面激波这一假设的合理性，说明了在激波未扰动区域（激波上游），物理量在几个小时内的变化很小这一事实，利用平面激波的分析方法，提出了分析模拟的行星际MHD激波的新方法，包括激波位置的确定，上下游状态参数的选择，激波局部参数的计算以及激波的分类，最后应用这种方法对一个二维的MHD模拟结果进行了分析。结果证实了过去文献关于磁流体力学混合激波空间连接和时间演化的链式规则，而且说明位于太阳赤道附近的慢激波和中间激波最终会发展为快激波。

A NEW APPROACH TO DETERMINE LOCAL PARAMETERS OF INTERPLANETARY SIMULATED MHD SHOCKS

Firstly it is accounted for the validity of the hypothesis that interplanetary MHD shocks can be treated as locally planar with no thicklless when analyzing their Iocal properties, and the fact is demoastrated that the variatious of the phys- ical quantities can be ignored in the area where no shock perturbs (in the upper reach of the shock) within a few hours. Then making use of the method to analyze planar MHD shocks. In doing so, a new approach is deveoped to detedrie local parameters of interplanetary simmulated MHD shocks. The proposed approach in- cludes defining the location of the shock, selecting the state parameters in the upper and lower reaches of the shock, computing the shock's local parameters, and classi- fying the shock according to its upstream and downstream Alfevn Mach numbers. Finally, the proposed method is used to deal with the result of a two-dimensional MHD simulation. The analyses confirm the linkage law of hybrid MHD shocks' spatial connection and temporal evolution in the past reference and reveal that the slow and intermediate shocks near the solar equator finally evolve into fast shocks during their outward propagation.