Interdisciplinary Graduate School of Engineering Sciences, Kyushu University, Kasuga 816-8580, Japan.
Phys Rev Lett. 2013 Jul 19;111(3):035002. doi: 10.1103/PhysRevLett.111.035002. Epub 2013 Jul 17.
In this Letter, we report analyses of spatiotemporal dynamics of turbulence and structure in the limit-cycle oscillation (LCO) that precedes an L-to-H transition. Zonal flows are not observed during LCO, and the oscillation is the periodic generations or decays of barrier with edge-localized mean flow. Oscillatory Reynolds stress is found to be too small to accelerate the LCO flow, by considering the dielectric constant in magnetized toroidal plasmas. Propagation of changes of the density gradient and turbulence amplitude into the core is also observed.
在这封信件中，我们报告了在 L 到 H 转变之前的限环振荡（LCO）中湍流和结构的时空动力学分析。在 LCO 期间未观察到纬向流，并且该振荡是具有边缘局域平均流的屏障的周期性产生或衰减。通过考虑磁化托卡马克等离子体中的介电常数，发现振荡雷诺应力太小，无法加速 LCO 流动。还观察到密度梯度和湍流幅度变化的传播进入核心。
