引江济淮五老堰跌水工程汇流口通航水流条件及改善措施

Navigable flow conditions and improvement measures at confluence of Wulaoyan water drop project for water diversion project from the Yangtze River to the Huaihe River

基于VOF法的RNG k-ε双方程紊流数学模型,对引江济淮工程五老堰跌水工程水力特性及下游通航水流流态进行三维数值模拟,研究汇流口通航区域横向流速及流态特征,分析原设计方案汇流口通航水流条件不满足规范要求的原因,并通过跌水工程后退、减小汇流角度和优化翼墙与干渠连接弧度等措施对原设计方案进行调整优化。结果表明,优化后的工程方案汇流口区域横向流速与回流流速均满足设计要求,5和20 a一遇通航工况最大回流流速分别为0.10和0.16 m/s,最大横向流速分别为0.13和0.27 m/s,可作为推荐方案。

Based on RNG k-εtwo equations turbulence mathematical model of VOF method,the hydraulic characteristics and downstream navigable flow pattern of the Wulaoyan water drop project of the Yangtze River to the Huaihe River diversion project are numerically simulated 3D,the transverse velocity and flow pattern characteristics of the navigable area at the confluence are studied,and the reasons why the navigable flow conditions at the confluence in the original design scheme do not meet the specification requirements are analyzed.The original design scheme is adjusted and optimized by measures such as retreating through water drop project,reducing the confluence angle and optimizing the connection radian between wing wall and main canal.The results show that the transverse flow velocity and return flow velocity in the confluence area of the optimized engineering scheme meet the design requirements.The maximum reflux velocities under the 5-year and 20-year navigation conditions are 0.10 m/s and 0.16 m/s respectively,and the maximum transverse velocities are 0.13 m/s and 0.27 m/s respectively,which can be used as the recommended scheme.