基于公式覆盖度的矩形渠道收缩断面水深计算

摘要

In order to improve the application scope of water depth formula at contracted section, firstly by simplifying the bas-ic water depth equation of contracted section in rectangular channel, we obtain the non-dimensional depth iteration equation, then replacing the cubic equation by simple unary quadratic equation and taking the root of unary quadratic equation as the initial value of the iteration equation, so the water depth calculation equation can be obtained consequently. It shows that when the non-dimensional depth at contracted section is less than 0. 6, the maximum relative error is 0. 15%. This equation has simple form, high accuracy and wide application range, which provides a new calculation method of water depth at contracted section un-der special conditions.%为了适当提高收缩断面水深公式的适用范围，通过对矩形渠道收缩断面水深的基本方程进行化简，得到无量纲水深迭代方程，随后采用一元二次方程替代矩形收缩断面水深的一元三次方程，最后将二次方程的解代入迭代方程中得到无量纲收缩断面水深的计算公式。该公式在无量纲收缩断面水深不大于0.6时，最大相对误差小于0.15%。公式具有形式简单、适用范围广、精度高的特点，为特殊工况下的断面水深计算提供了新的方法。