Computer Simulation of Earth's Magnetotail Dynamics

地球磁尾动力学的计算机模拟

• 批准号: 01540350
• 负责人: OGINO Tatsuki
• 金额: $ 1.28万
• 依托单位: Nagoya University
• 依托单位国家: 日本
• 项目类别: Grant-in-Aid for General Scientific Research (C)
• 财政年份: 1989
• 资助国家: 日本
• 起止时间: 1989 至 1990
• 项目状态: 已结题
• 来源: https://kaken.nii.ac.jp/grant/KAKENHI-PROJECT-01540350/
• 关键词: Magneto Hydrodynamics; Earth's Magnetosphere; Computer Simulation; Magnetic Reconnection; Helical Plasmoid; Magnetic flux rope; Boundary Layer; Instability phenomena; 太陽風磁気圏相互作用; 地球磁気圏ダイナミックス; 磁気圏境界層

For the first time. we carried out a global MHD simulation on the structure and dynamics of magnetotail depending on the orientation of the interplanetary magnetic field (IMF) in the plane of north-south, east-west. As a results, the magnetic neutral line forms in the plasma sheet for southward IMF and a hot plasma is ejected towards the tail. When there is a large east-west component of IMF during the southward interval of IMF, the magnetic field lines which confine hot plasma become a helical structure. Both edges of the helical plasmoid are gradually winded are concented to the earth's ionosphere as the helical plasmoid somewhat shifts towards the tail. Then a structure like magnetic flux rope, that confines a longitudinal magnetic field instead of plasma, appears between the ionosphere and the edges of the helical plasmoid. The tail reconnection proceeds in the whole plasma sheet region and the hot plasmoid is ejected tailward as a helical plasmoid when all the field lines are disconnected.Moreover we carried out a high resolution MHD simulation in two times grid points by introducing a newly developed MHD code in a modified leap-frog method in order to study a boundary layer phenomena. The thickness of magnetopause is thinner for southward IMF and it is thicker for northward IMF. Thiis is because the magnetic field varies mildly across the magnetopause for northward, on the other hand a high pressure plasma appears in the dayside neutral line to make thinner the magnetopause. When time elapses, the boundary layer (or magnetopause) has a wavy structure for the shake of dayside magnetic merging. The wavy structure enlarges the momentum transfer from magnetosheath to magnetopause.

首次。我们根据在东南部，东西方面的​​平面飞行道磁场（IMF）的方向进行了全球MHD模拟，具体取决于磁尾的结构和动力学。结果，磁中性线在血浆板上形成，用于向南的IMF，并将热等离子体驱逐向尾部。当在IMF的南部间隔内有IMF的大型东西方组件时，将热等离子体限制的磁场线成为螺旋结构。螺旋浆细胞的两个边缘逐渐发出，因为螺旋状浆体朝着尾部移动时，将螺旋形粘液液浓缩。然后，在电离层和螺旋浆细胞的边缘之间出现了构成纵向磁场而不是等离子体的磁通绳之类的结构。当所有野外线断开时，将尾部重新连接在整个浆液片区域进行，并将热等离子体弹出为螺旋浆样。此外，我们通过在修改后的Leap-Frog方法中引入一种新开发的MHD MOHD代码，以一种修改后的LEAP-Frog方法，以研究一种调整的LEAP-Frog方法，以研究一个高分辨率的MHD模拟，以研究一个新开发的MHD代码，以研究边界层次。磁胶的厚度对于南部的IMF较薄，对于北向IMF而言，它的厚度更厚。 Thiis是因为磁场在北向的磁磁磁场上略有变化，另一方面，高压等离子体出现在日子中性线上，以使磁磁磁性更薄。当时间过去时，边界层（或磁磁带）具有波浪结构，用于摇动白天的磁合并。波浪结构扩大了从磁石转移到磁场的动量转移。

项目成果

Tsuruda, K., and T. Okada et al: "Electric field Experiment (EFD)" Geotail Interrim Report (ISAS) ,. 33-54 (1990)

Tsuruda, K. 和 T. Okada 等人：“电场实验 (EFD)”Geotail 中期报告 (ISAS)。

Ogino, T., R. J. Walker, and M. Ashour-Abdalla: "Magnetic flux ropes in 3-dimensional MHD simulation" Geophysical Monograph Ser.Vol. 58. 669-678 (1990)

Ogino, T.、R. J. Walker 和 M. Ashour-Abdalla：“3 维 MHD 模拟中的磁通绳”地球物理专着 Ser.Vol。

Walker,R.J.,and T.Ogino: "“The fororation of isolated masnetic flux tubes on the dayside magnetopause"Electromasnetic Coupling in the Polar Clefts and Caps" Kluwer Academic Publishers, 11-26 (1989)

Walker, R.J. 和 T.Ogino：“日侧磁层顶上隔离磁通管的穿孔”极地裂隙和极帽中的电磁耦合”Kluwer 学术出版社，11-26 (1989)

Ogino,T.,R.J.Walker,and M.Asahour-Abdalla: "Magnetic flux ropes in 3-dimensional MHD simulations" Geophyscal Monograph Series. (1990)

Ogino,T.、R.J.Walker 和 M.Asahour-Abdalla：“3 维 MHD 模拟中的磁通绳”地球物理学专着系列。

Walker,R.J.and T.Ogino: "Global magretohydrodynamic sinulatrons of the nagnetosphere" IEEE Transaction on Plasma Science. 17. 135-149 (1989)

Walker,R.J. 和 T.Ogino：“磁层的全球磁流体动力学正弦子”IEEE 等离子体科学汇刊。