大沽河河道整治的准三维数值模型

Application of quasi-3D hydrodynamic numerical model to channel regulation scheme for Dagu River

大沽河下游河道蜿蜒曲折,淤积严重,河流动力数学模型对于选择合理的防洪减淤及蓄水通航措施具有重要意义。采用准三维水动力模型、全三维泥沙动力和河床演变模型,建立了青岛大沽河三维河流动力学模型。模型通过静压假定降低了三维模型的计算量,同时也反映了水流垂向流速差异及其对河床冲淤的影响。模型验证结果表明,洪水位和输沙总量的计算结果合理,模型可用于大沽河口的洪水和泥沙输运规律研究,为大沽河河道整治中选择最优闸坝位置、堤防形态、橡胶坝宽度以及码头断面形态优化等提供建议,实现防洪减淤、蓄水通航的最大效益。

The Dagu River suffers from the fluvial process in the recent years.A numerical model can be used to minimize the fluvial and flood water levels,and to optimize the water storage and navigation conditions.In this study,a quasi-3D numerical hydrodynamic model and a 3D fluvial model are combined to simulate the hydrodynamic and fluvial processes.The quasi-3D numerical model for the river dynamics shows a great advantage comparing with the 3D numerical model in the computation efficiency while retaining the capability for simulating the vertical distribution of the flow and sediment.Model calibration results show that the model calculated results of the flood stage and total sediment runoff are reliable and reasonable,which can be further used to study the flood control and siltation reduction as well as sediment transport in the Dagu River.These simulation results can provide suggestions for the optimization of the location of the dam,the shape of the embankments,the width of the rubber dam and the optimization of the cross-section of the Dagu River in order to realize the maximum benefit of the flood control,siltation reduction and water storage for navigation.