沁河高庄段洪水漫堤二维模拟

2D simulation of dike overtopping in Gaozhuang reach of Qinhe River

根据洪水传播和运动的特性,建立了适合沁河高庄段实际情况的二维数学模型.模型为非结构网格,采用单元中心的有限体积法求解控制水流运动的二维方程.应用此数学模拟方法模拟沁河高庄段洪水漫堤过程.确定了河道糙率,洪泛区选取不同糙率,用此二维模型对高庄河段100年一遇洪水进行模拟计算,得到洪水淹没范围及淹没水深和水流流速.高庄河段100年一遇洪水情况下的淹没深度、淹没面积和观测点淹没过程,可为风险分析和灾害损失评估提供参考依据.

Based on the analysis of transmission patterns and movement charateristics of the overtopping-dike flood,this paper proposes a 2D numerical model for the simulation of dike overtopping in the Gaozhuang reach of the Qinhe River.Both the unstructured grid method and the cell center finite volume method are applied to build the numerical model.Different methods are applied to selecting the roughness coefficients of the river channel and the floodplain.In the given model,a constant value is used in the case of roughness coefficient of the river channel,while different ones are selected in the floodplain case.Taking the flood with frequency of 1% for example,the simulating results,such as flood inundated area;inundated depth and flow velocity are obtained.The proposed model can reasonably predict the flood inundated area as well as reproduce the inundated depth widening and dike overtopping processes in the Gaozhuang reach of the Qinhe River;so as to give support for flood risk assessment and disaster loss evaluation.