Statistics of Lagrangian velocities in turbulent flows.
Statistics of Lagrangian velocities in turbulent flows.
复制标题
湍流中拉格朗日速度的统计。
DOI：
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发表时间：
2003
影响因子：
8.6
通讯作者：
R. Friedrich
中科院分区：
文献类型：
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作者：
R. Friedrich
我们提出了湍流中单个流体粒子的联合位置-速度概率分布的广义福克-普朗克方程。基于简单的估计，扩散项与两点两次欧拉加速度-加速度相关性有关。量纲分析产生速度增量概率分布，其正态缩放 v 约为 t(1/2)。然而，统计量不一定是高斯分布的。
We present a generalized Fokker-Planck equation for the joint position-velocity probability distribution of a single fluid particle in a turbulent flow. Based on a simple estimate, the diffusion term is related to the two-point two-time Eulerian acceleration-acceleration correlation. Dimensional analysis yields a velocity increment probability distribution with normal scaling v approximately t(1/2). However, the statistics need not be Gaussian.