摘要
试验资料表明,回流段流速及底部切应力横向分布沿流向呈自相似性。根据相似原理,水深平均方程可化为常微分方程,经求解获得了无量纲速度剖面公式。验证表阴,速度剖面公式不仅适用于垂线平均流速剖面,而且也适用于沿水深各流层速度剖面。利用速度剖面公式计算的垂线平均流速场与实测值符合较好。拟合了无量纲切应力剖面公式,探讨了主回流区阻力分布规律。 此外,还分析了影响回流长度的因素,建立了回流长度经验公式。
The velocity distribution and the bed shear stress distribution in the downstream of a step is found to be self-preserving along stream. Hence, the depth-average equation is transformed into an ordinary differential equation by similarity considerations. The formulas of dimensionless velocity-profile and dimensionless bed shear stress-profile are obtained. The dimensionless velocity-profile formula fits not only the depth average velocity profile but also velocity profile of each layer along depth. The computed results using the dimensionless velocity-profile formula are in close agreement with experimental data. The resistance characteristics of main and recirculating flow and the length of the recirculating flow arc also studied.
出处
《水动力学研究与进展（A辑）》
CSCD
北大核心
1992年第4期396-402,共7页
Chinese Journal of Hydrodynamics
基金
属"七五"攻关研究课题
关键词
回流
流速
切应力
单边突扩水流
recirculating flow, velocity, bed shear stress, self-preserving, length of recirculating flow,
