水力光滑明渠流流速分布的新公式

New formula for velocity profile of turbulent flow in open channel with smooth wall

采用一个新的湍流黏性模型研究水力光滑明渠流的流速分布,得到的结果与以往在明渠中所测的实验数据吻合较好。基于这个湍流黏性模型,推导出一个新的光滑明渠流外部区域的流速亏损规律,该表达式可以推广到内部区域,并提出一种新的确定内部区域流速分布的近似方法。运用本文给出的公式计算结果与由多普勒激光流速计所测的实验数据吻合良好。在只给出平均流速和水深的情况下,根据本文给出的公式可求得内外区域流速分布。

A new eddy viscous flow model for turbulent open channel flow considering the total turbulent viscous coefficient is proposed based on experimental data given by predecessors. The Reynolds number of the experimental data is ranging from 23 × 103 to 440 × 10^3 . Based on this model a new velocity deficit law is deduced and the velocity distribution can be obtained according to the average flow velocity. Furthermore, the velocity distribution of inner region of flow is established by introducing the empirical relationship for determining the related parameters. The new formula is in good agreement with the experimental data.