考虑下渗影响的洪水演进过程数值模拟研究

Numerical simulation of flood propagation process considering infiltration effect

为分析下渗对洪水演进的影响,选取城市洪水和天然河道洪水为研究对象,采用基于二维动力波的方法耦合了水文及水动力过程的数值模型,模拟分析了不同来流条件下洪水演进时的淹没过程。研究发现:在涨水阶段,下渗对于淹没面积影响不大;在退水阶段,考虑下渗的淹没面积明显小于不考虑下渗的淹没面积,即在退水阶段下渗对洪水淹没面积影响较大。分析两个研究对象发现,下渗对于城市洪水演进相较于天然河道洪水演进的影响更小。该研究成果对防洪防汛、洪水灾后救援有指导意义。

To analyze the influence of infiltration on flood propagation,urban flood and natural channel flood were selected as research objects,with the dynamic wave based numerical model coupled with hydrologic and hydrodynamic process adopted to simulate and analyze the inundation process of flood evolution under different inflow conditions.The results show that infiltration has little influence on the inundation area in the flood stage.In the recession stage,the inundation area with infiltration is significantly smaller than that without considering infiltration,that is,infiltration in the recession stage has a greater impact on the inundation area.By analyzing the two research objects,it is found that infiltration has less influence on urban flood propagation than on natural channel flood propagation.The research results are of guiding significance for flood control and rescue after flood.