Numerical simulation of drift waves and trapped ion modes
Numerical simulation of drift waves and trapped ion modes
复制标题
漂移波和俘获离子模式的数值模拟
DOI：
10.1063/1.870629
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发表时间：
1994
影响因子：
2.2
通讯作者：
R. Waltz
中科院分区：
文献类型：
--
作者：
O. T. Kingsbury;R. Waltz
采用二维数值模拟方法研究了俘获电子漂移波（DW）和俘获离子模（TIM）的相互作用。波数（k）空间在对应于离子反弹频率的极向波数处被划分为长波区域和短波区域。两个场模型被用来描述捕获的电子漂移波动力学在短波和捕获的离子模式动力学的长波。标准情况具有曲率效应和碰撞性。耦合两个区域的非线性包括类似于有限拉莫尔半径（FLR）极化漂移的捕获离子香蕉宽度效应。本研究的主要结果是，TIM不有助于扩散显着，无论模型的非线性耦合到DW。这一结论是支持一个更一般的四场模型，包括压力动态，并允许离子温度梯度（ITG）驱动的漂移模式。当碰撞度变化时，扩散偏离γ/k2 x方程。
Two‐dimensional numerical simulations are used to study the interaction of trapped electron drift waves (DW) and trapped ion modes (TIM). Wave‐number (k) space is divided into long and short wave regions at a poloidal wave number corresponding to the ion bounce frequency. Two field models are used to describe trapped electron drift wave dynamics at short waves and trapped ion mode dynamics for long waves. The standard case has curvature effects and collisionality. The nonlinearity that couples the two regions includes a trapped ion banana width effect analogous to finite Larmor radius (FLR) polarization drift. The principal result of this study is that the TIM do not contribute to the diffusion significantly, regardless of the model for the nonlinear coupling to the DW. This conclusion is supported by a more general four field model that includes pressure dynamics and which allows ion temperature gradient (ITG) driven drift modes. When the collisionality is varied, the diffusion deviates from the γ/k2x fo...