Gupta D K, Fonck R J, McKee G R, Schlossberg D J, Shafer M W
University of Wisconsin-Madison, 1500 Engineering Drive, Madison, Wisconsin 53706, USA.
Phys Rev Lett. 2006 Sep 22;97(12):125002. doi: 10.1103/PhysRevLett.97.125002. Epub 2006 Sep 21.
A low-frequency, spectrally broad (Deltaf approximately 10 kHz) poloidal flow structure that peaks near zero frequency is observed in time-resolved measurements of the turbulence velocity field in the core region (r/a approximately 0.6-0.9) of DIII-D tokamak plasmas. These flows exhibit a long poloidal wavelength (low m) and a short radial coherence length comparable to the ambient turbulence decorrelation length. Characteristics of these observed poloidal flows are consistent with the theoretically predicted residual or zero-mean-frequency zonal flows.
在DIII-D托卡马克等离子体核心区域（r/a约为0.6 - 0.9）的湍流速度场的时间分辨测量中，观察到一种低频、频谱宽广（Δf约为10 kHz）的极向流结构，其在接近零频率处达到峰值。这些流表现出长的极向波长（低m值）和短的径向相干长度，与周围湍流去相关长度相当。这些观测到的极向流的特征与理论预测的残余或零平均频率带状流一致。
