基于水动力学模型的沿海城市洪水实时演进模拟

为了准确分析洪涝灾害对防洪体系现状的影响,做出相应的防洪减灾措施,以浙江省台州市灵江下游流域为研究区域,构建了基于Saint-Venant方程的水动力学耦合模型,对河道溃决洪水过程进行实时仿真模拟。综合考虑研究区域地形、气象、水文资料、水利工程、下垫面条件等因素,在一维河网模型和二维水动力学模型耦合衔接中,最大程度还原真实地形中河槽内外的水流交互淹没,借助研究区域内典型台风暴雨资料,率定验证本文建立的一维-二维耦合水动力学模型,检验后的模型可实现灵江下游沿岸城市不同量级设计洪水及历史洪水的实时淹没过程模拟。模型计算结果表明,该模型模拟复杂地形条件情况下流域洪水实时演进过程达到了较高精度,在水系沿程典型断面水位计算值与实测值误差不超过0.1 m。

Real-Time Flood Routing Simulation of Coastal Cities Based on Hydrodynamic Model

With the acceleration of urbanization, urban flood and waterlogging disasters are frequent. In order to accurately analyze the impact of flood disasters on the current flood control system and make corresponding measures for flood control and disaster reduction, the lower reach of Ling River along the southeast coast is taken as the research area in this paper. We construct a hydrodynamic coupling model based on Saint-Venant equation, and simulates the process of river burst flood in real time. Considering the factors of the study area such as topography, meteorology, hydrological data, hydraulic engineering, underlying surface conditions and so on, in the coupling connection of one-dimensional river network model and two-dimensional hydrodynamic model, the interactive inundation of water flow inside and outside the river channel in real terrain can be restored to the greatest extent. With the help of typhoon and rainstorm data in the study area, the one-dimensional and two-dimensional coupled hydrodynamic models established are calibrated and validated. The tested models can be used to simulate the real-time submergence of design flood and historical flood in Coastal cities along the lower reaches of Ling River. The results show that the model has good accuracy in simulating the real-time flood routing process under complex terrain conditions, and the error between the calculated value and the measured value of typical section water level along the river system is less than 0.1 m.