Nonlinear theory and angular spectrum of the ion‐acoustic instability
Nonlinear theory and angular spectrum of the ion‐acoustic instability
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离子声不稳定性的非线性理论和角谱
DOI：
10.1063/1.1694550
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发表时间：
1973
影响因子：
4.6
通讯作者：
B. Bezzerides
中科院分区：
文献类型：
--
作者：
A. Sleeper;J. Weinstock;B. Bezzerides
提出了电流驱动离子声不稳定性的非线性理论。饱和机制是湍流波对离子轨道的扰动，从而导致离子与波之间的共振相互作用加宽。计算了角谱和有效值场的起伏能，并与实验和二维计算机模拟进行了比较。在三维空间中得到的角谱的近似表达式预测了一个宽的角谱以及与最近的两个实验一致的数量级的涨落水平。更完整的二维数值结果也预测了一个与二维模拟相一致的宽角谱，以及一个与模拟相一致的涨落水平。
A nonlinear theory of the current‐driven ion‐acoustic instability is presented. The saturation mechanism is the perturbation of the ion orbits by the turbulent waves, which results in a broadening of the resonant interaction between the ions and the waves. The angular spectrum and rms field fluctuation energy are calculated and compared both with experiment and two‐dimensional computer simulations. An approximate expression for the angular spectrum, obtained in three dimensions, predicts a broad angular spectrum as well as a fluctuation level which is in order of magnitude agreement with two recent experiments. More complete numerical results in two dimensions also predict a broad angular spectrum in agreement with the two‐dimensional simulations, and a fluctuation level in very good numerical agreement with the simulations.