摘要
采用一维时变MHD模型,系统地研究了压力扰动在行星际空间的传播.结果表明:(1)压力扰动在行星际空间发展成为快激波对和接触间断,其中密度扰动和持续时间较短的温度扰动,可能导致慢激波的形成;(2)激波和接触间断的强度随扰动幅度的增长而变强,形成位置则随扰动持续时间变短而提前;(3)随着扰动持续时间的增长,快激波强度增强,慢激波强度反而减弱;(4)快激波主要受温度扰动控制,而慢激波则主要受密度扰动控制.
This paper presents a systematical study of the propagation of pressure disturbances in the interplanetary space by using a one dimensional, time dependent MHD model. The main conclusions are as follows. (1)A pressure disturbance evolves into a fast shock pair and a contact surface while propagating in the interplanetary space, and may lead to the formation of slow shocks for a pure density disturbance or a temperature disturbance of short duration. (2)The strength of shocks and contact surface increases with increasing disturbance amplitude whereas the location of their formation moves towards the sun with decreasing disturbance duration. (3)The fast shock strengthens and the slow shock weakens with increasing disturbance duration. (4)The fast and slow shocks are controlled mainly by disturbances in temperature and density respectively.
基金
国家自然科学基金
关键词
行星际动力学
压力扰动
激波
interplanetary dynamics, pressure disturbance, shock