明渠弯道交汇口水动力特性数值模拟  

Numerical simulation of hydrodynamics of open-channel confluences with bend flow

作　　者：曾诚[1] 尹雨然 陈辰 周婕 邱斐 白一墨 王玲玲[1] ZENG Cheng;YIN Yuran;CHEN Chen;ZHOU Jie;QIU Fei;BAI Yimo;WANG Lingling(College of Water Conservancy and Hydropower Engineering,Hohai University,Nanjing 210098,China;College of Mechanics and Materials,Hohai University,Nanjing 211100,China)

机构地区：[1]河海大学水利水电学院,江苏南京210098 [2]河海大学力学与材料学院,江苏南京211100

出　　处：《水利水电科技进展》2023年第2期9-15,38,共8页Advances in Science and Technology of Water Resources

基　　金：国家重点研发计划(2022YFC3202605);中央高校基本科研业务费专项(B200202116,B200204044)。

摘　　要：为研究不同宽深比和径宽比对明渠弯道交汇口水动力特性的影响规律,利用体积函数法(VOF)追踪自由表面,采用RNG k-ε模型封闭控制方程,建立明渠弯道交汇水流三维数值模型对3种宽深比和3种径宽比的5种组合工况进行了模拟,分析了交汇口附近的水面形态、流速分布、断面环流和分离区形态等特征。结果表明:随着宽深比的增大或径宽比的减小,交汇口附近水面跌落程度减弱;与径宽比相比,宽深比对弯道交汇口以及下游区域内流速分布的不均匀性影响较大,宽深比增大,纵向流速变幅增大,流速分布更加不均匀,水流偏转效应增强;宽深比或径宽比减小导致弯道处环流强度增大;宽深比或径宽比增大,弯道处回流结构增强,分离区尺寸增大,水平方向上形态更加狭长。In order to study the impacts of different width-depth ratios and radius-width ratios on the hydrodynamic characteristics at open-channel confluences with bend flow,a three-dimensional numerical model was established by using the volume of fluid(VOF)method for the free surface capture and adopting the RNG k-εmodel for the governing equations closure.The water surface pattern,velocity distribution,secondary flow and shape of separation zone were analyzed after the simulations of five combined cases with three width-depth ratios and three radius-width ratios.The results indicate that the degree of water level drop near the intersection decreases with the increase of the width-depth ratio or the decrease of the radius-width ratio.Compared to the radius-width ratio,the width-depth ratio has a stronger impact on the non-uniformity of velocity distribution at the confluence and the downstream area.When the width-depth ratio increases,the longitudinal flow rate increases and the non-uniformity of velocity distribution increases with enhanced flow deflection effect.When the width-depth ratio or radius-width ratio increases,the reflux structure at the bend is enhanced,the size of the separation zone increases with narrower and longer horizontal form.

关 键 词：明渠弯道水流 支流入汇 宽深比 径宽比 数值模拟 

分 类 号：TV131.2[水利工程—水力学及河流动力学]