Configurations of the solar wind flow and magnetic field around the planets with no magnetic field : calculation by a new MHD simulation scheme
Configurations of the solar wind flow and magnetic field around the planets with no magnetic field : calculation by a new MHD simulation scheme
复制标题
DOI：
10.1029/93ja01516
复制
发表时间：
1993-10
影响因子：
--
通讯作者：
T. Tanaka
中科院分区：
文献类型：
--
作者：
T. Tanaka
在非结构网格系统上采用有限体积总变差递减格式发展了一种新的MHD模拟方案，并将其应用于太阳风-行星相互作用问题，假设行星周围的电离层是理想导电的。计算结果表明，本文提出的方法能有效地计算行星附近三维MHD流的位形和磁场的叠加过程。计算结果对弓形激波、磁垒、磁鞘、磁层顶、尾流区、等离子体片和磁尾的形成给出了一般的确认。由于J × B力的作用，在太阳风速度磁场（VB）坐标系中，行星附近的气流在极地加速，在赤道面减速。在尾区，J × B力的作用是加速午夜子午面的流动，抑制尾激波的形成。然而，目前的计算给出了一个较弱的大小为尾部磁场比所给出的观测，并建议一些额外的机制的作用，在尾部的磁场堆积。
A new MHD simulation scheme is developed on an unstructured grid system using the finite volume total variation diminishing scheme and applied to the problem of solar wind-planet interaction, assuming a perfect-conducting ionosphere around the planet. It is shown that the scheme presented here enables one to calculate effectively the configuration of three-dimensional MHD flow near planets, together with the draping process of magnetic field. Results of the calculation give a general confirmation for the formations of the bow shock, the magnetic barrier, the magnetosheath, the magnetopause, the wake region, the plasma sheet, and the magnetotail. Because of the J × B forces, flow near the planet is accelerated in the polar regions and decelerated in the equatorial plane in the solar wind velocity magnetic field (VB) coordinate system. In the tail region, the J × B forces act to accelerate the flow in the midnight meridian plane and suppress the formation of the trailing shock. However, the present calculation gives a weaker magnitude for the tail magnetic field than that given by the observations and suggests the role of some additional mechanisms for the pileup of the magnetic field in the tail.