基于二维网格边元设置河道方法的蓄滞洪区洪水演进分析

大型蓄滞洪区洪水数值模拟往往涉及众多中小河道,需要构建一二维耦合水动力学模型。针对传统一二维耦合方式建模及计算效率低的问题,本文基于二维网格边元设置河道的方法构建了一二维耦合模型;并选择海河流域大陆泽、宁晋泊蓄滞洪区为典型应用区域,对该方法进行了应用检验;同时根据构建好的模型分析了下渗对于蓄滞洪区洪水演进的影响。研究结果表明下渗会显著减小蓄滞洪区洪峰水位,缩短淹没时间,在蓄滞洪区实际调度使用中应该考虑下渗的影响;模型的成功应用表明基于边元设置河道的耦合方式可以有效地计算蓄滞洪区中小河道与地面水流的交互过程,模型具有较好的应用推广价值。

Application of a new 1D-2D numerical model coupling strategy to flood simulation in flood storage-detention areas

A 1D-2D coupled hydrodynamic model is often necessary in numerical simulations of large flood storage-detention areas because of the existence of rivers. Aiming at the problem of low computational efficiency of traditional coupling method,a coupling strategy that the rivers are generalized on the two-dimensional cell edges is proposed and applied in the Daluze and Ningjinbo,a typical flood storage-detention area in Haihe River Basin. The influence of the infiltration on the flood routing is also analyzed based on the calibrated model. The results show that the infiltration will significantly reduce the peak water level and flooding time,and the successful application of the model shows that the present coupling strategy can effectively calculate the flow interaction between river and ground,thus having a good potential for popularization.