挑流消能水工模型试验及挑距、冲刷坑深度估算方法

Hydraulic Model Test of Ski-Jump Energy Dissipation and Flip Nappe Distance and Scour Pit Depth Estimation Method

通过溢洪道水工模型试验,优化了溢洪道挑流鼻坎体型结构,在拟合冲刷坑计算表达式中引入鼻坎体型系数作为挑射角角度的影响参数,通过量纲分析、回归分析,推求确定各相关参数。结果表明,在下游河床地质条件相同时,影响冲刷坑深度的因素主要有鼻坎处单宽流量、流速、上下游水位落差、鼻坎体型等,提出的冲刷坑计算公式较现行规范中公式的计算精度明显提高,更接近实测值。

The cubic construction of spillway flip bucket was optimized based on the spillway hydraulic model test.The shape coefficient of the nostril was taken as the influencing parameter of the projection angle,in the calculation expression of fitting scour pit.The relevant parameters were deduced through dimensional analysis and regression analysis.The results show that the main factors affecting the depth of scour pit are the discharge per unit width,flow velocity,water level difference between upper and lower reaches of the ridge and the shape of the ridge when the geological conditions of the river bed downstream are the same.The calculation precision of the formula presented in this paper is obviously higher than that in the current code,and it is closer to the measured value.