基于水文水动力学耦合的洪水预报模型研究及应用

为了提高下垫面变化剧烈流域的洪水预报精度,在传统流域水文模型的基础上耦合水动力学模型,建立水文水动力耦合洪水预报模型。首先利用水文模型获得某一断面的流量过程作为水动力学模型的边界条件;之后利用一维水动力学模型进行河道洪水演进计算,推求流域出口断面的流量过程;最后以烟台市外夹河流域为例进行验证。结果表明,所建水文水动力耦合模型模拟的产流合格率较高,流量过程与实测值吻合,在一定程度上弥补了集总式水文模型不能考虑河道内复杂水流运动的不足,因此对具有复杂水文、水力条件的流域的洪水预报具有重要的指导意义。

Study and application of a flood forecasting model based on coupled hydrological-hydrodynamic approach

In order to improve the accuracy of flood forecasting in basins with dramatic changes in the base course, this paper proposes a coupled hydrological-hydrodynamic flood forecasting model which couples the traditional hydrological model with the one-dimensional hydrodynamic model. First, the flow process of a section was obtained by the hydrological model and was used as the boundary condition of the one-dimensional hydrodynamic model. Then the one-dimensional hydrodynamic model was applied to simulate the flood routing in the river channel. The proposed method was tested on the Waijia River basin in Yantai City, China. The results indicate that the coupled model can simulate runoff yield with a high qualification rate, and generate flow processes that tally with the measured values. It can be concluded that this coupled hydrological-hydrodynamic model may make a significant contribution to flood forecasting in basins with complex hydrologic and hydraulic conditions thanks to its ability to model water movement in the basin.