Zonal flow generation in parallel flow shear driven turbulence
Zonal flow generation in parallel flow shear driven turbulence
复制标题
DOI：
10.1063/1.4978485
复制
发表时间：
2017-03
影响因子：
2.2
通讯作者：
Y. Kosuga;S. Itoh;K. Itoh
中科院分区：
文献类型：
--
作者：
Y. Kosuga;S. Itoh;K. Itoh
讨论了平行流切变驱动湍流中纬向流的产生。非线性动力学是通过计算波数空间中的能量传递来建立的。结果表明，在平行流切变的驱动下，主模态可以产生纬向流（获得能量）。因此，在紊流等离子体中可以形成螺旋流型。我们的研究结果表明，在三维平行流剪切驱动的湍流中可以产生纬向流，这表明无论在二维还是三维湍流等离子体中，纬向流都是普遍存在的。讨论了实验室和天体物理等离子体湍流动量输运的意义。
Generation of zonal flow in parallel flow shear driven turbulence is discussed. Nonlinear dynamics is formulated by calculating energy transfer in the wave number space. It is shown that zonal flows can be generated (gain energy) from the primary mode which is driven by parallel flow shear. As a result, helical flow pattern can develop in turbulent plasmas. Our results imply that zonal flow can be generated in 3D parallel flow shear driven turbulence, which indicates that zonal flows are ubiquitous in turbulent plasmas, either 2D or 3D. Implications for turbulent momentum transport in laboratory and astrophysical plasmas are discussed.