径流与潮流对长江口泥沙输运的影响

Influence of Runoff and Tide on Sediment Transport in the Yangtze Estuary

本文首先建立了一个一维水流、二维泥沙数学模型，以长江口南港北槽为实际背景，研究了径流和潮流共同作用下，泥沙输运的规律；讨论了泥沙近底边界条件，认为非恒定情况下泥沙底边界条件应考虑沉降效应。分析了径流和潮流的不同组合，对长江口泥沙输运的影响。同时，对长江口实施整治工程后航道的变化进行了预测。

A one dimensional, vertical grid unsteady model is developed to study sediment transport in combined tide runoff flows around the Yangtze estuary. The model uses reference concentration as the bottom boundary condition for suspended sediment. It is suggested that the bottom boundary condition in unsteady flow should take the effect of sediment settling into consideration. The respective influences of runoff and tide have been carefully analysed. Finally, the topographic variation of waterway between north and south dykes is predicted.