基于体型参数组合的Y型宽尾墩水力特性

Hydraulic characteristic of Y-shaped flaring gate pier based on combination of body shape parameters

水流经过宽尾墩后由于收缩挤射,产生三面掺气的大曲率水气交界面,流态异常复杂.利用数值模拟方法对Y型宽尾墩体型参数变化时的水力特性进行了分析研究.采用逐步收敛法比较分析12种不同体型宽尾墩泄流时的流态、水面线与流速分布、宽尾墩始折点处的佛汝德数及消能率等水力特性参数的变化规律.研究结果表明:随着宽尾墩收缩比增大,墩后水舌交汇点下部空腔增大,底流速整体上增大,佛汝德数增大,消能率略有降低;随着宽尾墩墩长增加,出闸水流的跌流趋势更加明显,流速增长加快,佛汝德数减小,消能率略有降低;随着上顶点与始折点高差增大,闸室内水面线升高且壅水效果更加明显,闸室内水流流速加大而消力池段流速反而减小,佛汝德数增大,消能率略有增加;随着始折点与上缩点高差增大,出闸水流纵向拉伸幅度降低,跌流趋势更加明显,佛汝德数增大,整体流速略微增大,消能率减小.

Been squeezed by flaring gate pier,water flow shots to the stilling basin and a large curvature waterair interface on the three sides of the aerated gas formed subsequently.The flow pattern is extremely complicated.The numerical simulation method is adopted to analyze the hydraulic characteristics of different body shape parameters of Y-shaped flaring gate pier.Stepwise convergence method is adopted to compare and analyze the changes of hydraulic parameters of 12 different types of flaring gate pier,such as flow patterns,water surface lines,velocity distributions,Froude number at the starting location of flaring gate pier,and energy dissipation rates.The results show that with the shrinkage ratio of the flaring gate pier increasing,the lower cavity of the junction of the water tongue behind the flaring gate pier increasing,the bottom flow velocity increasing,the Froude number increasing accordingly,and the energy dissipation rate decreasing slightly.With the increasing of the length of the flaring gate pier,the trend of the flow of the gate is more obvious,the flow rate increasing rapidly,the Froude number and the energy dissipation rate decreasing slightly.With the height difference between the upper vertex and the starting point increasing,the water surface line in the gate chamber is relatively increasing.The flow velocity in the sluice chamber is increasing,while the flow velocity in the stilling basin decreasing.The Froude number and the energy dissipation rate are increasing slightly.With the height difference between the starting point and the upper shrinkage point increasing,the longitudinal distance from flaring gate pier to point that water flow immersing with stilling basin becoming shorter,and the trend that water flow becoming drop flow is obvious,the overall flow velocity increasing slightly,the Froude number increasing,and the energy dissipation rate decreasing separately.