复杂山区暴雨洪水数值模拟方法研究

Numerical modeling for rainfall-induced flash flood in complex mountainous regions

针对具有复杂地形的暴雨山洪数值模拟,基于考虑降雨和下渗的二维浅水方程,采用Godunov型有限体积法,建立暴雨山洪二维水动力学数值模型,提出了新的水深重构方法,解决了复杂地形上暴雨山洪数值模拟常面临的计算水深小于零、非物理大流速等问题。算例研究结果表明,该模型计算稳定性好、计算效率高,具有较好的推广应用价值。

To simulate the rainfall-induced flash floods in complex mountainous regions, a hydrodynamic model is developed based on the two-dimensional shallow water equations with rainfall and infiltration, and the Goclunov- type finite volume method is used for numerical resolution. A new method of water depth reconstruction on sloping girds is proposed to resolve the problem of negative water depth and unphysical large velocity for simulation on complex topography. Numerical results of test examples show that the proposed model is stable and efficient, thus with bright application prospects.