Rayleigh–Taylor instability: Comparison of hybrid and nonideal magnetohydrodynamic simulations
Rayleigh–Taylor instability: Comparison of hybrid and nonideal magnetohydrodynamic simulations
复制标题
瑞利-泰勒不稳定性：混合和非理想磁流体动力学模拟的比较
DOI：
10.1063/1.872904
复制
发表时间：
1998
影响因子：
2.2
通讯作者：
D. Winske
中科院分区：
文献类型：
--
作者：
J. Huba;D. Winske
用混合码和非理想磁流体力学（MHD）码研究了低β二维等离子体中瑞利-泰勒不稳定性的演化。选择瑞利-泰勒不稳定性作为试验用例，是因为它是边界层上一个重要的混合过程，并且在常规极限和非理想极限下表现出不同的行为。考虑的非理想MHD效应是霍尔项和有限拉莫尔半径（FLR）修正。详细考虑了三种情况：常规MHD、弱非理想效应和强非理想效应。在传统的MHD状态下，通常观察到瑞利-泰勒不稳定性的“气泡和尖峰”行为。在弱非理想MHD状态下，长波长模式（类似于开尔文-亥姆霍兹不稳定性）在非线性中占主导地位，但在边界界面处形成非常短的波长细丝。在强非理想MHD区，小尺度结构占主导地位，边界层通过类似扩散的过程松弛。
The evolution of the Rayleigh–Taylor instability in a low β, two-dimensional plasma is studied using a hybrid code and a nonideal magnetohydrodynamic (MHD) code. The Rayleigh–Taylor instability was chosen as a test case because it is an important mixing process at boundary layers, and because it exhibits different behaviors in the conventional and nonideal limits. The nonideal MHD effects considered are the Hall term and finite Larmor radius (FLR) corrections. Three cases are considered in detail: conventional MHD, weak nonideal effects, and strong nonideal effects. In the conventional MHD regime the usual “bubble and spike” behavior of the Rayleigh–Taylor instability is observed. In the weak nonideal MHD regime long wavelength modes, reminiscent of the Kelvin–Helmholtz instability, dominate nonlinearly but very short wavelength filaments develop at the boundary interface. In the strong nonideal MHD regime, small-scale structures dominate and the boundary layer relaxes via a diffusion-like process rather ...