山丘区小流域洪水风险模型研究及应用

Study and Application of Flood Risk Analysis Model for Small Watershed in Hilly Area

一维水动力演进模型能快捷进行长河段洪水演进预报,二维演进模型能准确进行山丘区小流域水流运动的模拟,提供洪水淹没范围、淹没深度等信息。基于一维、二维演进模型的不同特点,提出基于无结构化网格划分流域计算网格的一、二维耦合山丘区小流域洪水风险分析模型。利用该模型对太平溪流域P=10%设计暴雨条件下的洪水进行模拟分析,制作该设计暴雨条件下太平溪流域的洪水风险图,并通过耦合模型分析、风险图成果利用,研究太平溪流域的洪水风险因素,提出洪水风险应对对策及措施。利用耦合模型进行洪水风险分析,将成为山丘区小流域洪水风险管理的一项重要技术支撑。

One-dimensional hydrodynamic evolution model can quickly carry out long river flood forecast. The two-dimensional evolution model can accurately simulate the flow of small watershed in the hilly area,and provide information such as flood submerged range and submerged depth.Based on the different characteristics of one-dimensional and two-dimensional evolution model,a one-dimensional and two-dimensional coupled flood risk analysis model based on unstructured grid is proposed. Taking the small watershed of Taipingxi Hill as an example,the model was used to simulate the flood under the rainstorm with P = 10% in the basin. The flood risk map of the Taipingxi basin under the heavy rain condition was made. By analyzing coupled model and using the risk graph results,the flood risk factors in the Taipingxi basin were studied,solutions and measures for flood risk were put forward. The use of coupled model for flood risk analysis will be an important technical support for flood risk management.