中文摘要：

侧堰作为一种量水设施,精度较高、结构简单、安装和拆卸方便,较易在灌区应用和推广,有很大的研究价值。对不同宽度和高度的矩形侧堰在缓流条件下进行了试验,分析了各工况下矩形渠道侧堰上、下游水面线、能量分布、流量系数等水力因素。结果表明,主渠道侧堰段能量基本保持不变,符合De Marchi的恒定能量假定;主渠道靠近侧堰边壁、中心线以及另一边壁三处的水面波动程度不同,说明侧堰对堰前水流产生影响;基于De Marchi假定和无量纲分析原理得到的流量公式最大相对误差均在±10%以内,满足灌区量水精度要求。

英文摘要：

Side weir is a widely used water-measuring device due to its simplicity in shape, easeto install and- move as well as high precision. Experiment was conducted to test the hydraulic characteristics of wire with different widths and heights under subcritical flow condition. Water profiles and energy distribution in the upstream and downstream of the weir, as well as the discharge coefficient were analyzed. The results show that the energy in the main channel is constant, meeting the De Marchi ＇ s assumption of constant energy. Water-surface wave on the wall near the side weir, the centerline and the wall in the main channel differ, indicating that the flow in front of the weir is independent of the side weir. Based on the De Marchi＇ s assumption of constant energy and the principle of dimensional analysis, we obtained discharge formulae. The maximum relative errors of the formulae are less than 10%, meeting the accuracy of flow measurement in irrigation district.