考虑复杂河工建筑物的漫堤洪水一、二维水动力耦合模型

Coupled 1D-2D Hydrodynamic Model for Overflow Flood Considering Complex River Buildings

针对景观坝和过水路面等河工建筑物严重影响河道排洪泄洪问题,基于MIKE FLOOD平台构建漫堤洪水一、二维水动力耦合模型,模拟分析复杂河工建筑物壅水与漫溢洪水淹没演进过程。采用Abbott六点隐式格式和显式有限体积法分别离散求解一、二维水流运动方程,利用干湿水深理论优化模型运算效率,将河道内过水路面与景观坝作为宽顶堰概化处理,同步计算桥涵淹没出流。将模型应用于宁夏茹河(店洼水库至小河河口)河道跨河工程阻水效果及漫堤洪水的数值模拟。结果表明,模拟结果较真实地反映了河工建筑物对水流的阻碍效应及桥涵动态过流效果。研究成果可为宁夏茹河及其他类似河道的整治工程规划设计及风险评价提供参考。

As some hydraulic structures such as landscape dam and waterway seriously hinder flood flow, a coupled one and two-dimensional hydrodynamic model was developed based on the MIKE FLOOD software to simulate water blocking effect about the hydraulic structures and the routing process of overflow flood. The Abbott six-point implicit scheme and the finite volume method were used to solve the equations of one dimensional and two dimensional flow respectively. Drying and wetting fronts theory was used to optimize the efficiency of the model. The synchronous calculations was used to solve the submerged discharge of bridge and culvert in the model. The model was applied to the numerical simulation of water blocking effect about the hydraulic structures and the flood of the embankment in the Ruhe River in Ningxia. The results reflects the obstructive effect of the river structure on the river flow and the dynamic glide effect of the bridge and culvert. The research results have certain reference value for the planning design and risk evaluation of Ruhe River in Ningxia and other similar areas.