梯形断面明渠丁坝绕流水力特性三维大涡模拟  

3D numerical simulation of hydraulic behaviors of spur dike flow in a trapezoid open channel

作　　者：魏文礼[1] 邵世鹏[1] 刘玉玲[1] 

机构地区：[1]西安理工大学水利水电学院,陕西西安710048

出　　处：《西安理工大学学报》2015年第4期385-390,共6页Journal of Xi'an University of Technology

基　　金：国家自然科学基金资助项目(51178391);陕西省科学研究计划基金资助项目(2014K15-03-05);陕西省西北旱区生态水利工程重点实验室开放基金项目(106-221223);中央财政支持地方高校发展专项资金特色重点学科项目(106-00X101)

摘　　要：对梯型断面明渠非淹没式单一丁坝绕流水力特性进行三维数值模拟,为丁坝的设计和施工提供理论基础支持。数值模拟采用两相流混合模型,并分别选取大涡模型(LES)和RNG k-ε湍流模型封闭两相流时均方程。速度与压力的耦合使用半隐式SIMPLE算法,模拟自由水面采用了VOF法。通过不同截面流线图和流速矢量图的比较得出大涡模型能更好地捕获水流瞬时流动特性,动态再现二次流动结构;并将其模拟的丁坝后回流区域边界线与试验值对比,两者吻合良好,表明大涡模型能够很好地模拟明渠丁坝绕流的水力特性分布规律。The 3-D numerical computation of flow hydraulic behaviors around non-submerged spur-dikes in a trapezoid open channel is carried out to provide theoretical basis support for design and construction of spur-dikes.The gas-liquid two-phase large eddy simulation and the gas-liquid two-phase mixture model with 3-D RNG k-εturbulence model are used in the simulation.The SIMPLE algorithm is used to solve velocity and pressure.The VOF method is used to simulate the free surface.The comparisons of the streamlines at different section simulated by the large eddy simulation and RNGk-εmodel show that the large eddy simulation can better capture the instantaneous flow behaviors and can simulate dynamic secondary flow structures.The comparisons of the biggest recirculation boundary line between the computed and the measured data are in a good agreement,which indicates that the large eddy simulation can well simulate the hydraulic characteristics of spur dike flow in trapezoid open channel.

关 键 词：丁坝绕流 数值模拟 大涡模型 RNG k-ε模型 水力特性 

分 类 号：TV131.4[水利工程—水力学及河流动力学]