明渠均匀流研究

Study on the uniform flow in open channel

利用普朗特-卡门(Prandtl-Karman)粗糙平板上的流速分布公式,推出了二维明渠均匀流的流速计算公式;然后,在假定矩形渠道底部阻力和边墙阻力相等的条件下,推出了矩形明渠均匀流的流速计算公式;随后,利用尼古拉兹的粗糙管道流阻力系数公式,推出半圆形明渠满流时的计算公式,再转化为非满流条件下的计算公式。将推导出来的二维、矩形及半圆形明渠计算公式的计算结果同前人的试验结果相对比,二者吻合良好;并同谢才-曼宁公式的计算结果进行对比,结果表明,文中4个算例的计算结果比谢才-曼宁公式的计算结果更接近试验值。

Based on the Prandtl-Karman velocity distribution on the rough plate, the authors obtained the formulas for calculating velocity of two dimensional uniform flows in open channel. Supposes the resistance coefficient of bottom is equal to that of side wall, the velocity formula for rectangular channel is obtained. Afterwards, we obtain the formula for the full channel flow in semi-circle channel based on the resistance coefficient formula of rough pipe flow of Nikuradcs, and then transform it to that for the slack flow. Com- parison of the results of the deduced formulas to the previous test studies, they are in good agreement. Firther comparing it with the Ch6zy-Manning formulas, the computation results of the formulas for the four examples are much better than those based on the Ch6zy-Manning formulas.