连续弯道水流模拟中二次流修正效果评价  

Comparative evaluation of secondary flow correction methods for consecutive bend flow simulation

作　　者：周刚[1] 姚仕明[2] 秦翠翠[3] 贾鹏 

机构地区：[1]中国环境科学研究院国家环境保护河口与海岸带环境重点实验室,北京100012 [2]长江科学院水利部江湖治理与防洪重点实验室,湖北武汉430010 [3]清华大学水沙科学与水利水电工程国家重点实验室,北京100084 [4]环境保护部环境工程评估中心国家环境保护环境影响评价数值模拟重点实验室,北京100012

出　　处：《水科学进展》2016年第2期266-279,共14页Advances in Water Science

基　　金：长江科学院开放研究基金资助项目(CKWV2012303/KY);国家自然科学基金资助项目(51109194)~~

摘　　要：为了选择适用于复杂连续弯道的二次流修正方法,选取了线性方法中两种典型的计算模式,通过在正交曲线坐标系二维浅水动量方程中增加扩散应力项开发了考虑二次流影响的平面二维水流模型。基于不同复杂度的4个连续弯道试验的水位和流速分布资料,通过理论分析和数值试验对比定量评估了传统二维模型和两种二次流修正方法在连续弯道水流模拟中的效果。测试结果表明,Delft3D模型的二次流修正方法自由度较高,适用于不同复杂度的连续弯道水流模拟,而Lien模型二次流修正方法适用于微弯或中弯,应用于中弯时需要慎重选用,不适用于急弯连续弯道模拟。两种方法比较,建议连续弯道水流模拟中优选Delft3D模型的二次流修正方法。Secondary flow has a substantial influence on water flow,mass transportation and riverbed evolution. However,conventional 2-D depth-averaged models usually ignore the influence of secondary flow. Furthermore,the suitability of existing secondary flow correction models is debatable. To select a secondary flow correction method that can be applied to complex consecutive bends,two typical linear model calculation schemes,the Delft3 D and Lien methods,are evaluated. The influence of secondary flow is considered in the 2-D depth-averaged models proposed in this paper by calculating the dispersion stresses added to the 2-D shallow water momentum equations in orthogonal curvilinear coordinates. Four unique consecutive curved flume experiments were chosen to evaluate the simulation effects.The evaluations compared the simulated water levels and velocity distributions for a conventional 2-D model and two kinds of secondary flow correction methods. Analysis of the simulation results demonstrates that the performance of the Delft3 D secondary flow correction method is the better of the two methods tested. The method has higher degrees of freedom and is suitable for different complexity levels of consecutive bend simulations. While Lien＇ s secondary flow correction method is not suitable for sharp consecutive bend flow simulations,it can be used effectively to simulate weak or moderate bends,however,care should be taken for consecutive bends of moderate curvature. Therefore,comparison of the two methods shows that the Delft3 D modeling method is the better choice for simulating flow in consecutive bends.

关 键 词：二次流 扩散应力 连续弯道 二维模型 急弯 

分 类 号：TV143[水利工程—水力学及河流动力学]