Xu Haitao, Bourgoin Mickaël, Ouellette Nicholas T, Bodenschatz Eberhard
Laboratory of Atomic and Solid State Physics, Cornell University, Ithaca, New York 14853, USA.
Phys Rev Lett. 2006 Jan 20;96(2):024503. doi: 10.1103/PhysRevLett.96.024503. Epub 2006 Jan 19.
We report measurements of the Lagrangian velocity structure functions of orders 1 through 10 in a high Reynolds number (Taylor microscale Reynolds numbers of up to R(lambda) = 815 ) turbulence experiment. Passive tracer particles are tracked optically in three dimensions and in time, and velocities are calculated from the particle tracks. The structure function anomalous scaling exponents are measured both directly and using extended self-similarity and are found to be more intermittent than their Eulerian counterparts. Classical Kolmogorov inertial range scaling is also found for all structure function orders at times that trend downward as the order increases. The temporal shift of this classical scaling behavior is observed to saturate as the structure function order increases at times shorter than the Kolmogorov time scale.
我们报告了在高雷诺数（泰勒微尺度雷诺数高达(R(\lambda)=815)）湍流实验中对1到10阶拉格朗日速度结构函数的测量结果。通过光学手段在三维空间和时间上跟踪被动示踪粒子，并根据粒子轨迹计算速度。结构函数反常标度指数通过直接测量以及使用扩展自相似性来测量，结果发现它们比对应的欧拉指数更具间歇性。对于所有结构函数阶数，还发现了经典的柯尔莫哥洛夫惯性范围标度，其随阶数增加而呈下降趋势。当结构函数阶数在短于柯尔莫哥洛夫时间尺度的时间增加时，观察到这种经典标度行为的时间偏移会饱和。
