Energy dynamics in a simulation of LAPD turbulence
Energy dynamics in a simulation of LAPD turbulence
复制标题
LAPD 湍流模拟中的能量动力学
DOI：
10.1063/1.4759010
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发表时间：
2012
影响因子：
2.2
通讯作者：
B. Dudson
中科院分区：
文献类型：
--
作者：
B. Friedman;T. Carter;M. Umansky;D. Schaffner;B. Dudson
线性大等离子体装置中漂移波湍流三维流体模拟的能量动力学计算[j]。Gekelman等人，Rev. Sci。[j] .光学学报，1999,17(1):1 - 2。这些计算表明，非线性不稳定性通过超越线性漂移波不稳定性而主导着向湍流中注入能量，而线性漂移波不稳定性在围绕平衡的波动较小时占主导地位。非线性不稳定性利用来自背景密度梯度的自由能驱动笛状（k∥=0）密度波动。非线性不稳定通过非线性轴向波数传递到k∥≠0涨落，进入绝热响应，提供了从密度到势涨落所必需的能量传递通道以及引起不稳定的相移。模拟得到的湍流特性与实验结果非常吻合。当非线性不稳定性被人为地从系统中移除时…
Energy dynamics calculations in a 3D fluid simulation of drift wave turbulence in the linear Large Plasma Device [W. Gekelman et al., Rev. Sci. Instrum. 62, 2875 (1991)] illuminate processes that drive and dissipate the turbulence. These calculations reveal that a nonlinear instability dominates the injection of energy into the turbulence by overtaking the linear drift wave instability that dominates when fluctuations about the equilibrium are small. The nonlinear instability drives flute-like (k∥=0) density fluctuations using free energy from the background density gradient. Through nonlinear axial wavenumber transfer to k∥≠0 fluctuations, the nonlinear instability accesses the adiabatic response, which provides the requisite energy transfer channel from density to potential fluctuations as well as the phase shift that causes instability. The turbulence characteristics in the simulations agree remarkably well with experiment. When the nonlinear instability is artificially removed from the system through ...
影响因子：
6.3
作者：
Dudson, B. D.;Umansky, M. V.;Wilson, H. R.
通讯作者：
Wilson, H. R.