一维—二维耦合的水库下游地区洪水演进数学模型及应用

针对水库下游地区河道洪水与漫堤洪水模拟需求,建立了一维—二维耦合的洪水演进数学模型。一维模型采用Pressimann格式离散求解,二维模型采用能够适应复杂几何形状和多种流态的Osher格式求解,一维—二维连接处采用堰流公式实现水流交互。应用该模型模拟白溪流域2015年"苏迪罗"台风实际洪水,可得到洪水在计算区域的演进过程和淹没情况。对比模拟结果与实际情况可知,该模型计算合理、准确,计算结果可为防汛部门防洪预案制定、防汛调度决策提供技术支撑。

1D-2D Coupled Mathematical Model for Numerical Simulation of Flood Routing in Downstream of Reservoir and Its Application

A 1D-2D coupled hydrodynamic model was established for the requirements of flood routing in flood protected zone of the river flood and the downstream of reservoir. Preissmann implicit scheme was used to solve 1D model. 2D model was solve by the Osher method, which is suitable for the complex geometry shape and multiple flow regimes. The flow interaction among the coupling of two models was handled by the weir flow equation. The model was applied to simulate the actual "Sudie" typhoon flood that occurred in Baixi basin in 2015, which obtained the flood wave propagation and flood inundation area in calculation area. The model was proved to be reasonable and accurate by comparing the simulation results with the actual situation. The study provides technical support for making flood control planning and flood scheduling decision.