任意多边形网格2D FVM模型及其在城市洪水淹没中的应用

2D FVM Model Based on an Arbitrary Polygonal Mesh System for the Simulation of Flood Inundation and Its Application in Municipal Regions

为了减轻城市因溃堤、水库溃坝、或超标洪水而引起的巨大财产损失与人员伤亡,准确模拟计算这类洪水的时空演进规律就显得特别重要。然而,城市区域内的各类构筑物常因形态各异、边界复杂,计算中如何考虑其影响成为研究者必须面对的一大问题。为此,基于二维浅水波方程,提出了任意多边形网格有限体积离散的洪水模拟模型。通过在日本富士川流域内甲府盆地的实际应用,验证了该数值模拟模型,结果也表明:该模型运行可靠、精度较高、能更好地反映洪水波的运动特性,更适合评价城市洪水风险与损失、研制防洪风险图、预警系统和应急预案。

In order to mitigate the loss of live and property in a municipal region due to a dyke-break or dam-break or extremely large flood, it is very important to accurately simulate the movements and distributions of flood in both the temporal and the spatial domains. However, irregular structures and complex inner and outer boundaries within a municipal region can make the simulation complicated. Therefore, a 2D FVM flood simulation model based on arbitrary polygonal mesh system to discretize the 2D shallow water equations is proposed. The numerical simulation model is validated through its application in the Fuji River basin of the central Japan. Results indicate that the simulation model is stable, accurate and easy to capture the properties of flooding waves, and that the model is also suitable for the assessment of flood risks and losses in municipal regions, for the development of hazard maps, flood warning systems and emergency plans.