Research Institute for Applied Mechanics, Kyushu University, 6-1 Kasuga-Koen, Kasuga-city, 816-8580, Japan.
Sci Rep. 2012;2:860. doi: 10.1038/srep00860. Epub 2012 Nov 15.
Physics of turbulence and turbulent transport has been developed on the central dogma that spatial gradients constitute the controlling parameters, such as Reynolds number and Rayleigh number. Recent experiments with the nonequilibrium plasmas in magnetic confinement devices, however, have shown that the turbulence and transport change much faster than global parameters, after an abrupt change of heating power. Here we propose a theory of turbulence in inhomogeneous magnetized plasmas, showing that the heating power directly influences the turbulence. New mechanism, that an external source couples with plasma fluctuations in phase space so as to affect turbulence, is investigated. A new thermodynamical force in phase-space, i.e., the derivative of heating power by plasma pressure, plays the role of new control parameter, in addition to spatial gradients. Following the change of turbulence, turbulent transport is modified accordingly. The condition under which this new effect can be observed is also evaluated.
湍流和湍流输运的物理特性一直基于一个中心法则，即空间梯度构成控制参数，如雷诺数和瑞利数。然而，最近在磁约束装置中的非平衡等离子体实验表明，在加热功率突然变化后，湍流和输运的变化速度比全局参数快得多。在这里，我们提出了一种非均匀磁化等离子体湍流理论，表明加热功率直接影响湍流。研究了一种新的机制，即外部源与等离子体在相空间中的涨落耦合，从而影响湍流。在相空间中，一个新的热力学力，即等离子体压力对加热功率的导数，作为除空间梯度之外的新控制参数发挥作用。随着湍流的变化，湍流输运也相应地被修正。还评估了可以观察到这种新效应的条件。
