移动网格下黄河下游游荡段二维水沙数值模拟  

Two-dimensional numerical simulations of water-sediment transport in lower Yellow River wandering reach based on moving grids

作　　者：张志鸿[1] 彭杨[1] 罗诗琦 姚礼双 ZHANG Zhihong;PENG Yang;LUO Shiqi;YAO Lishuang(School of Water Resources and Hydropower Engineering,North China Electric Power University,Beijing 102206,China)

机构地区：[1]华北电力大学水利与水电工程学院,北京102206

出　　处：《水力发电学报》2022年第8期30-41,共12页Journal of Hydroelectric Engineering

基　　金：国家重点研发计划项目(2016YFC0402502);国家自然科学基金项目(51679088)。

摘　　要：本文针对游荡型河道水沙数值模拟中岸滩崩塌引起的网格移动问题,采用任意拉格朗日-欧拉方法,在正交贴体坐标系中建立了移动网格下的黄河下游游荡段平面二维非恒定水沙数学模型,同时为使移动网格情况下水沙运动控制方程满足几何守恒律,推导了正交贴体坐标系下网格运动项的计算公式,并采用基于弧长的超限插值法,提出了一种能追踪河岸边界变化的网格移动计算方法。最后采用黄河下游花园口至高村河段2013年实测水沙资料对模型进行验证,结果表明,本模型能较好地模拟出计算河段的水沙输移、滩槽冲淤分布和岸滩冲刷后退过程,所建模型可用于黄河下游游荡型河道水沙运动和滩槽演变模拟。To address the issue of moving grids adapted to intense bank erosion in a wandering river reach,a two-dimensional mathematical model is developed based on moving grids and an orthogonal curvilinear body-fitted coordinate system using the arbitrary Lagrangian-Eulerian method,aimed at the unsteady flow and sediment transport in a wandering reach of the lower Yellow River.Then,for the grid moving terms of the basic equations of flow and sediment transport under the orthogonal curvilinear body-fitted coordinates,a new formula is derived that allows the equations to obey the geometric conservation law.We also develop an approach to moving the grid nodes on the moving boundary through an algorithm of transfinite arc length interpolation.Finally,we verify this new model against the 2013 measurements of the wandering reach between Huayuankou and Gaocun.The results demonstrate that this grids-moving model is able to reproduce flow and sediment transport,river bed aggradation and degradation,and bank-floodplain scour and retreat in the studied wandering reach,and that it is also applicable to the other lower Yellow River reaches.

关 键 词：河流动力学 岸滩崩塌 二维水沙数学模型 移动网格 任意拉格朗日-欧拉方法 游荡段 黄河下游 

分 类 号：TV147[水利工程—水力学及河流动力学]