A generalized Hasegawa?Mima equation in curved magnetic fields
A generalized Hasegawa?Mima equation in curved magnetic fields
复制标题
弯曲磁场中的广义长谷川?美马方程
DOI：
10.1017/s0022377822000514
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发表时间：
2022
影响因子：
2.5
通讯作者：
Yamada Michio
中科院分区：
文献类型：
--
作者：
Sato Naoki;Yamada Michio
通过分析弯曲几何形状对离子流体极化漂移速度的影响，导出了描述一般（非均匀和弯曲）磁场中静电等离子体湍流的模型方程。导出的非线性方程推广了均匀直磁场中漂移波湍流的Hasegawa-Mima方程，可以作为描述湍流等离子体的玩具模型。该方程最适用于漂移速度较小的构型。我们确定了系统的守恒能量，得到了广义涡度拟能守恒的磁场拓扑条件。通过数值例子，我们进一步展示了磁场的曲率如何重塑自组织稳定的湍流状态。
We derive a model equation describing electrostatic plasma turbulence in general (inhomogeneous and curved) magnetic fields by analysing the effect of curved geometry on the ion fluid polarization drift velocity. The derived nonlinear equation generalizes the Hasegawa–Mima equation governing drift wave turbulence in a straight homogeneous magnetic field, and may serve as a toy model for the description of turbulent plasmas. The equation is most appropriate for configurations with a small drift velocity. We identify the conserved energy of the system, and obtain conditions on magnetic field topology for conservation of generalized enstrophy. Through numerical examples, we further show how the curvature of the magnetic field reshapes self-organized steady turbulent states.