使用基于动态程序规划的时间延迟法分析直线磁化等离子体漂移波湍流角向传播速度和带状流结构

对等离子体湍流速度场的有效探测,有助于更加深入了解磁约束等离子体湍流以及实现对某些理论预言现象和结构(如带状流)的充分辨识.本文将基于动态程序规划的时间延迟估算技术成功应用于直线磁化等离子体装置中热阴极放电条件下的漂移波湍流角向速度涨落的实验分析,并且其结果清晰再现了漂移波湍流中通过非线性能量耦合自发产生的带状流结构.通过对采用不同频段等离子体湍流涨落通过基于动态程序规划的时间延迟估算分析所再现的带状流结构特征进行比较,进一步就该算法对载波信号中非相干噪声相对水平的抗干扰能力进行了定性评估.这些工作的成功开展,对于通过采用基于动态程序规划的时间延迟估算分析技术更为深入有效探索磁约束等离子体湍流行为特征,尤其是速度涨落场的演化提供了重要的借鉴和参考价值.

Analysis on the azimuthal velocity fluctuation of drift-wave turbulence and zonal flow via dynamic programming based time-delay estimation technique in a linear magnetized plasma device

The effective measurement of plasma turbulence flow field is of great help for better understanding the turbulence in magnetically confined plasmas, and experimentally verifying the theoretically predicted phenomenon such as zonal flows. In this article, the dynamic programming based time-delay estimation technique is employed for the first time to estimate azimuthal velocity fluctuation of drift-wave turbulence in a linear magnetized plasma generated via a hot cathode plasma source. Analysis results clearly reproduce the zonal flow structure which is spontaneously generated by nonlinear energy transfer from the drift-wave turbulence. Moreover, via the comparison among the zonal flow (ZF) characteristics estimated respectively by the turbulent fluctuations of plasma located in different frequency regions, we further evaluate the dependences of accuracy and response for estimating ZF property using this newly developed time-delay estimation algorithm on the level of relative incoherent noise in the carrier waves. This work provides an example and reference value for deeper exploration on plasma turbulence and in particular the relevant flow field with the help of the dynamic programming based time-delay estimation technique.
Keywords： dynamic programming based time-delay estimation zonal flow drift-wave turbulence velocity fluctuation