摘要
本文从三维恒定雷诺方程式出发导出了计算二维均匀明渠高含沙水流紊流极限切应力τＢＴ的公式．公式中包含了紊动扩散系数εｍ，并通过分析天然河道实测资料和室内水槽试验资料研究了εｍ沿垂线分布的规律，结论是明渠高含沙水流的紊动扩散系数εｍ沿垂线分布规律和低含沙水流的类似，在河底处εｍ为０；在河底至相对水深０．２范围内εｍ随水深增加而变大，在相对水深０．２至水面范围内εｍ为常数．用所得τＢＴ计算公式对部分天然河道实测资料进行验算，大多数明渠高含沙水流属紊流流态。
In this paper, a formula for calculating turbulent limit stress τBT for hyperconcentrated sediment flow in open channel is derived from Reynold's equation for two-dimensional steady and uniform turbulent flow. The distribution of the relative turbulent diffusion coefficient εs/ u H along the depth is studied by analyzing the data obtained from flume experiments and field observations. The figure drawn shows that εs / u H is zero on the bed and is increasing with the depth in the region from river bed to relative depth H/y = 0.2, while in the region from H/ Y= 0.2 to the free surface εs / u H is a constant. It is found that, in many cases the turbulent limit stress τBT is zero for hyperconcentrated sediment flow in open channel.
出处
《水利学报》
EI
CSCD
北大核心
1995年第12期54-58,共5页
Journal of Hydraulic Engineering
关键词
明渠
高含沙水流
紊流
扩散
turbulent limiting stress, bingham limiting stress, sediment turbulent diffusion, momentum turbulent diffusion.
