Weirs are commonly used for controlling, measuring, and regulating water flow in conveyance structures such as canals or dams. In this study, hydraulic properties of flow over broad-crested weirs including the effects of different sloping crests and upstream and downstream ramps were characterized by using the finite volume method. Numerical simulations were validated by experimental results; the numerical simulations are very similar to the experimental results. The discharge coefficient (C_d) for the broad-crested weir with upstream and downstream ramps and positive slope of crest (BCW-UDR-PSC) and the broad-crested weir with upstream and downstream ramps and negative slope of crest (BCW-UDR-NSC) are higher than the broad-crested weir with upstream and downstream ramps and horizontal crest (BCW-UDR-HC). It was found that for both the BCW-UDR-NSC and the BCW-UDR-PSC, the C_d increases with steeper weir crest slope. This shows that the C_d is affected by the slope of the crest such that the negative sloped crest more significantly increases the C_d than a positive slope. The average increase in value of the C_d for the BCW-UDR-NSC with respect the BCW-UDR-PSC is approximately 8%.

堰通常用于控制、测量和调节输送结构（如运河或水坝）中的水流。在这项研究中，使用有限体积法表征了宽顶堰上流动的水力特性，包括不同坡顶和上下游坡道的影响。数值模拟得到了实验结果的验证；数值模拟与实验结果非常相似。排出系数（C ^ _d用于与上游和下游斜面和波峰（的正斜率的宽顶堰）BCW-UDR-PSC）中，用上游和下游斜面和波峰的负斜率（宽顶堰BCW-UDR -NSC) 高于带有上下游斜坡和水平坝顶的宽顶堰 ( BCW-UDR-HC )。发现对于BCW-UDR-NSC和BCW-UDR-PSC，C _d随堰顶坡度的增加而增加。这表明C _d受波峰斜率的影响，因此负倾斜波峰比正斜率更显着地增加了C _d。在的值的平均增加Ç _d为BCW-UDR-NSC相对于BCW-UDR-PSC是约8％。