灌溉排水学报2017，Vol.36Issue(11)：51-55,5.DOI:10.13522/j.cnki.ggps.2017.11.010
基于拉格朗日法的抛物线形复合渠道的水力最佳断面
Calculating Optimal Channel Cross Section with Parabolic Slope and Flat Bed Using the Lagrangian Method
摘要
Abstract
Channels with parabolic cross section are deep and widely open, not suitable for use in medium-large canals. In this paper, we present a channel with parabolic slopes and flat bed and then calculated its hydraulic pa-rameters. Taking water depth and widths of water surface and channel bed as variables, we calculated the relation-ship between flow rate and water depth after optimizing the channel cross section using the Lagrangianiterative method and the Mathcad software. The dependence of wetting perimeter of the channel on water depth and widths of water surface and channel bed was also analyzed. Numerical calculations showed that when the optimal flow rate was 12 m3/s, the associated water depth was 2.263 m, the width of water surface was 4.538 m, and the cross-section area for water flow was 7.463 m2. This means a reduction in water-flow cross section by 1.67%com-pared to trapezoidal cross section, 0.84% compared to cross section with trapezoidal slopes and parabolic bed, and 1.05%compared toparabolic cross section.关键词
渠道/水力最佳断面/拉格朗日乘数法/水力计算Key words
channel/optimal hydraulic section/Lagrange multiplier method/hydraulic calculation分类
农业科技引用本文复制引用
李刚,何武全,翟东汉..基于拉格朗日法的抛物线形复合渠道的水力最佳断面[J].灌溉排水学报,2017,36(11):51-55,5.基金项目
国家"十三五"重点研发课题(2016YFC0400203) （2016YFC0400203）
