溃坝洪水演进一维水动力模型  

One-Dimensional Hydrodynamic Model for Dam-Break Flooding

作　　者：吕佳豪 侯精明 李东来 荆海晓[1] 陈光照 LYU Jiahao;HOU Jingming;LI Donglai;JING Haixiao;CHEN Guangzhao(State Key Laboratory of Eco-hydraulics in Northwest Arid Region of China,Xi an University of Technology,Xi an 710048,China)

机构地区：[1]西安理工大学西北旱区生态水利国家重点实验室,西安710048

出　　处：《山地学报》2024年第1期123-131,共9页Mountain Research

基　　金：国家自然科学基金(52079106);中德科学基金交流中心项目(M-0427);陕西省创新能力支撑计划-创新人才推进计划(2020TD-023)。

摘　　要：中国是受洪水灾害影响最严重的国家之一。洪水数值模型可准确地反映洪水的演进与致灾过程。本研究针对天然河道洪水过程存在的尺度大、水流流态复杂、河道断面形式多变以及计算建模困难等问题,提出一套基于Godunov格式的有限体积法离散圣维南方程组的一维水动力模型,并采用求解复杂断面水力要素之间关系的方法,提高了一维水动力模型求解的精度与效率,精确地反映了复杂断面河道的水流运动特性。将模型模拟得到的数值解与算例中的解析解或实测数据进行对比,结果表明:(1)构建的一维水动力模型模拟结果与理想算例解析解及实验实测数据吻合程度均较高,所有算例的E NS均大于0.5,说明模型具有良好的稳定性和适应性;(2)将模型应用至金沙江白格堰塞湖溃坝洪水算例中,模拟得到的流量峰值及整体洪水过程均与实测过程吻合较好,在叶巴滩和苏洼龙两个测点处E NS分别为0.633和0.812,证明了模型在实际应用中的适用性与可靠性。结果表明,开发的一维水动力模型对溃坝洪水等水流流态复杂、突发性强的洪水过程具有良好的模拟效果。本研究可为河道及溃坝洪水风险的初步、快速评估等工作提供有效的模拟支撑。China is one of the countries severely affected by floods.Numerical modelling of flooding can accurately reflect the flood evolution and disaster-causing process.In this study,a set of one-dimensional hydrodynamic model based on the finite volume method to discretize Saint-Venant equation set in Godunov format was proposed to address the issues of modeling of flooding in natural rivers characterized by large scale,complex flow regimes,variable channel cross-section forms;it employed a method for solving the relationships between hydraulic elements of arbitrarily complex cross-sections,which accurately provided values of hydraulic elements for any complex channel cross-section during model solving.(1)All cases had ENS values greater than 0.5,demonstrating the model s good stability and adaptability.By comparison the analytical solutions obtained by the model with solutions from classical ideal cases,experimental cases,and actual engineering cases,as well as measured data,this model improved the accuracy and efficiency of one-dimensional hydrodynamic model solving,effectively reflecting the characteristics in open-channel flow with complex cross-sections.(2)Applying this model to an actual example of dam-break flooding at the Baige Dam on the Jinshajing River,the simulated peak floods and overall flood processes closely match observations.ENS values at the two measurement sites,Yebatan and Suwalong were 0.633 and 0.812,respectively,convincing the applicability and reliability of the model in practical applications.The proposed one-dimensional hydrodynamic model exhibited excellent simulation effectiveness in flooding with complex flow conditions and high suddenness.This study provides an efficient simulation for preliminary or rapid assessment of dam-break flooding risks.

关 键 词：河道水动力模型 Godunov格式 明渠水流运动过程 复杂断面处理 溃坝洪水 

分 类 号：TV133.2[水利工程—水力学及河流动力学]