洪河倒虹吸交叉工程河段二维水沙数值模拟

南水北调中线工程总干渠与洪河交叉的倒虹吸工程,对天然河道洪水演进及河床变形产生了影响.采用平面二维水沙数学模型,依据历史洪水调查资料对模型进行调试和验证,按未修建洪河倒虹吸的自然工况及修建洪河倒虹吸的设计工况两种边界条件对工程交叉河段进行了典型洪水的水沙数值模拟,模拟计算给出了工程附近洪水水位、流速及冲刷深度等水力要素特征值.计算结果分析表明:倒虹吸工程位置选择合适,底宽布置及埋置深度基本合理.

2D water and sediment mathematical modeling for crossing project reaches of Honghe River inverted siphon

The main channel in the Middle Route of South-to-North Water Transfer Project passes through the Honghe River in forms of the inverted siphon project in Henan province,which has an effect on flood routing and river-bed deformation in the natural condition.In the present study,a two-dimensional hydrodynamic model reflecting terrain characteristics in the calculated reach has been established,which is calibrated and validated based on survey data of the historical flood.Then,the model is applied to conduct the numerical simulation of typical floods under the different conditions and some hydraulic elements such as water level,flow velocity and erosion depth near the project are obtained and compared.The simulated results show that the location of inverted siphon project is appropriate;and its embedded depth and bottom width layout are reasonable.