基于水动力模型的高精度动态洪水实时推演系统

Development of high-precision dynamic real-time flood simulation system based on hydrodynamic models

摘要:

为提升区域洪水模拟与风险评估能力,构建高精度水动力模型,以内蒙古科尔沁左翼后旗境内东、西辽河为研究对象,基于多尺度高分辨率河道地形数据,对河道主槽与滩地进行精细识别,构建河道二维水动力模型,模拟洪水在河道内的演进过程;同时,针对堤防满溢及溃堤等典型情景,建立一维河道与二维地表耦合的水动力模型,模拟洪水漫溢及淹没过程。基于2024年"7·21"典型洪水过程对模型进行率定与验证,结果表明:模拟水位与实测数据吻合良好,能够较准确地反映洪水传播过程及淹没特征。在此基础上,进一步构建研究区高精度动态洪水实时推演系统,模拟东辽河和西辽河300、800和1 500 m³/s流量情景下的洪水演进,分析河道滩地淹没、河道堤防保护区的淹没范围,实现模型成果向实际防洪业务的转化。研究成果能够有效支撑区域洪水风险识别与防洪避险决策,具有较强的工程应用价值与推广意义。

Abstract:

To enhance regional flood simulation and risk assessment capabilities, a high-precision hydrodynamic model was constructed. The study focused on the East Liao River and West Liao River within Horqin Left Rear Banner, Inner Mongolia. Based on multi-scale high-resolution topographic data, the main channel and floodplain were accurately identified, and a two-dimensional hydrodynamic model was established to simulate flood evolution within the river channel. In addition, to account for typical scenarios such as levee overtopping and levee breach, a coupled one-dimensional river and two-dimensional surface flow model was developed to simulate flood overflow and inundation processes. The model was calibrated and validated using the July 21, 2024 ("7·21") flood event. The results showed that the simulated water levels agree well with observed data, demonstrating that the model can accurately reproduce flood propagation and inundation characteristics. On this basis, a high-precision dynamic real-time flood simulation system was further established for the study area to facilitate the transformation of modeling outcomes into practical flood control applications. Flood routing simulations were then conducted for the East Liao River and West Liao River under discharge scenarios of 300 m³/s, 800 m³/s, and 1 500 m³/s, and inundation conditions of river floodplains and river levee protection zones were analyzed. The findings indicate that the proposed approach can effectively support regional flood risk identification and flood prevention decision-making and has strong engineering applicability and broader implementation potential.