底坡变化对坡面流水动力学特性影响研究

Research on influence of bottom slope variation on hydraulic characteristics of slope flow

坡度是影响坡面流水动力学特性的重要因素之一,采用变坡试验水槽在变化水深条件下模拟坡面流,用于研究7种不同坡度对水动力学特性的影响。结果表明:水力坡度、弗劳德数、雷诺数随坡度增大而增大,阻力系数随坡度增大先增大后减小;在相同坡度条件下,弗劳德数随水深增大先减小后趋于稳定,雷诺数随水深增大而增大;当0≤J≤1.5%时,水力坡度随水深增大先减小后趋于稳定;当2%≤J≤3%时,水力坡度随水深增大先基本不变后减小。

Slope ratio is one of the important factors affecting the hydrodynamic characteristics. Variable- slope flume test was conducted to simulate the slope flow of different water depth,and the influences of 7 different slope ratios on hydrodynamic characteristics were studied. The results showed that the hydraulic gradient,Froude number and Reynolds number of slope flow increase with slope ratio,the resistance coefficient increases with the slope at first and then decreases. For the same slope,it was concluded that Froude number increases with depth at first and then decreases to stable,Reynolds number increases with water depth increase; for 0 ≤J≤1. 5%,the hydraulic gradient decreases with water depth at first and then stabilizes; for 2% ≤J≤3%,the hydraulic gradient remains unchanged and then decreases with the increase of water depth.