Numerical modeling for rainfall-induced flash flood in complex mountainous regions
Zhang Yihong1, Song Lixiang2, Xie Jiabi3,4
(1. Shenzhen Dongshen Electronic Co. LTD,Shenzhen 518057;
2. Pearl River Hydraulic Research Institute,Guangzhou 510611;
3. China Institute of Water Resources and Hydropower Research,Beijing 100038;
4.Research Center on Flood and Drought Disaster Reduction of MWR,Beijing 100038)
Abstract: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 Godunov-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.