洪泛区洪水泥沙数学模型的研究和应用

Research and Application for Mathematical Model of Flood and Sediment in Flood Area

洪泛区暴雨洪涝灾害是一个严重的问题,伴随着暴雨洪涝,洪水泥沙等沉积物淤积问题突出。采用数值模拟的方法解决暴雨洪水滞涝及泥沙淤积问题。利用二维水流模型理论和二维泥沙运动理论,建立了适用于洪泛区的洪水泥沙输移数学模型。模型由两部分组成,洪水滞涝水动力模型和洪水泥沙输运数学模型。洪水滞涝水动力模型采用加权质量集中的有限单元法求解二维水流方程,泥沙输运数学模型采用时间前差的有限差分法求解二维悬沙运动方程和泥沙淤积方程。模型计算结果在一定精度范围内很好的和实测资料吻合。证明了该模型的可靠性。能够较好的模拟洪泛区的洪水泥沙情况。

The flood disaster in a flood area is a serious problem.Accompanied by flood,the problem of sediment deposition is also serious.The numerical simulation method is used here to solve the problems of flood waterlogging and sediment deposition.The 2-D flow model and 2-D sediment movement theory are also used to establish the mathematical model for sediment transport brought by flood.The model is consisted of two parts,e.g.,the hydrodynamic model for flood waterlogging and the mathematical model for flood sediment transport.In the hydrodynamic model,the finite element method of weighted quality cocentration is used to solve the 2-D flow equation,and in the mathematical model,the finite difference method of forward-different time is used to solve the 2-D suspended sediment motion equation and sediment deposition equation.The model result in a certain accuracy range is very good and consisted with the measured data,which would prove the model＇s reliability.The model could better simulate the situation of flood and sediment in a flood area.