一、矩形渠道侧堰的理论分析假定在侧堰附近主渠的断面比能为一常数(即渠道长度很短),如图1所示,任一断面的比能为:式中,H为断面比能,h为水深,v为主渠的断面平均流速,g为重力加速度。如果设b为主渠的渠宽,Q为沿主渠轴向任一断面的流量,则: I. Theoretical Analysis of Rectangular Channel Weir Assuming that the cross-section ratio of the main channel near the weir can be constant (that is, the channel length is short), as shown in Figure 1, the specific energy of any section is: where H is Cross section specific energy, h is the depth of water, v is the average flow velocity of the section of the main channel, g is the acceleration of gravity. If b is the width of the main canal and Q is the flow of any section along the axial direction of the main canal, then: