Bifurcation in electrostatic resistive drift wave turbulence
Bifurcation in electrostatic resistive drift wave turbulence
复制标题
静电电阻漂移波湍流中的分岔
DOI：
10.1063/1.2796106
复制
发表时间：
2007
影响因子：
2.2
通讯作者：
R. Dewar
中科院分区：
文献类型：
--
作者：
R. Numata;R. Ball;R. Dewar
Hasegawa-Wakatani方程，通过近似平行电子运动的物理学耦合等离子体密度和静电势，是描述电阻漂移波湍流的简单模型。对模型中的分岔现象进行了数值分析，为研究托卡马克等离子体边缘区湍流与纬向流的相互作用提供了新的思路。模拟结果表明，在初始瞬态后，漂移波湍流通过纬向流产生被抑制的制度。作为一个参数控制的湍流强度进行调整，这种带状流为主的状态迅速被破坏，并重新出现的湍流为主的状态。过渡解释的Kelvin-Helmholtz稳定性的纬向流。这是电阻漂移波系统中湍流开始上移的第一次观察，这类似于由离子温度梯度驱动的湍流中的众所周知的迪米特移位。
The Hasegawa-Wakatani equations, coupling plasma density, and electrostatic potential through an approximation to the physics of parallel electron motions, are a simple model that describes resistive drift wave turbulence. Numerical analyses of bifurcation phenomena in the model are presented, that provide new insights into the interactions between turbulence and zonal flows in the tokamak plasma edge region. The simulation results show a regime where, after an initial transient, drift wave turbulence is suppressed through zonal flow generation. As a parameter controlling the strength of the turbulence is tuned, this zonal-flow-dominated state is rapidly destroyed and a turbulence-dominated state re-emerges. The transition is explained in terms of the Kelvin-Helmholtz stability of zonal flows. This is the first observation of an upshift of turbulence onset in the resistive drift wave system, which is analogous to the well-known Dimits shift in turbulence driven by ion temperature gradients.