溢洪道差动式挑坎水力特性分析和计算探讨

溢洪道差动式挑流鼻坎可增大其挑射水舌的扩散、碰撞、掺气和消能率，从而减轻下游河床的冲刷。目前对差动式挑坎水力特性研究成果仍较少，给工程设计带来极为不便。在现有的文献和成果总结和分析的基础上，开展了差动式挑坎下游河床冲刷特性的试验研究，对差动式挑坎段的水面线、挑射水舌挑距及其下游河床冲刷特性和计算方法进行探讨，并进一步补充了差动式挑坎下游冲刷影响系数与其体型和泄流水力参数的关系。研究成果与水力模型试验结果较吻合，可供类似工程设计和运行参考。

Calculation discussion and analysis on hydraulic characteristics of spillway differential flip bucket

Differential flip bucket of spillway can increase collision, turbulence, aeration and energy dissipation rate of nappe, thus greatly reduce scour depth of the downstream river bed. At present, the study results of the hydraulic characteristics of differential flip bucket is still less, which is very inconvenient for the engineering design. Based on the summary and analysis of existing literatures and results, and the experimental study of the downstream river bed scour depth of differential flip bucket has been carried out, the hydraulic characteristics and calculation method of water surface profile, nappe distance and scour depth of the river bed of the differential flip bucket are discussed, and the relationship between the influence coefficient of the downstream scour and its body size and the discharge hydraulic parameters is further added. The results are in good agreement with the results of hydraulic model test, which can provide reference for similar engineering design and operation.