开敞式变坡溢洪道消能工数值计算分析

Numerical computation analysis on energy dissipation of the open space spillway with variable slope

采用紊流模型,VOF方法对三孔泄洪工况下,溢洪道全程流场进行了水气二相流三维数值模拟。特别在上游水库进口断面上自编程序使用了水位边界条件,计算得到校核水位下溢洪道沿程一系列水力要素,把溢洪道中心线压强、侧墙水面线以及水舌挑距与相应的模型实测值进行了验证。在此基础上,对收缩段水流冲击波,水舌入水宽度,入水角度、流速分布等水力特征进行了分析讨论。研究表明:三孔同时泄洪,在收缩段会出现较强的M型冲击波,随后在直段发展为◇型波;数值计算对于水舌入水宽度和入水角的模拟欠佳。

Under the condition of three-hole flood discharge,the three-dimensional numerical simulation of water-gas two-phase flow in spillway is carried out by using turbulence model and VOF method.In particular,the water level boundary condition is used in the self-compiled program on the inlet section of the upstream reservoir,and a series of hydraulic elements along the spillway under the checked water level are calculated.Firstly,the pressure of the center line of the spillway,the water surface line of the side wall and the pick-up distance of the water tongue are verified with the corresponding measured values of the model.On this basis,the hydraulic characteristics such as flow shock wave,water tongue entry width,entry angle and velocity distribution in the shrinkage section are analyzed and discussed.The results show that when three holes discharge flood at the same time,there will be a strong M-type shock wave in the contraction section,and then develop into a wave in the straight section,and the numerical calculation is not good for the simulation of water tongue entry width and entry angle.