河口节制闸下淤积及冲淤效果耦合模型计算

Analysis of deposition in downstream area of regulating gates at estuaries and modeling water flushing effect by coupled model

在潮汐作用下河口地区具有挡潮功能的节制闸闸下引河泥沙淤积现象十分普遍,泥沙淤积严重影响了其行洪排涝能力,危害极大.因此,研究闸下淤积规律、探讨科学的清淤措施具有重要的工程实践意义.分析闸下淤积规律,并预估了闸下淤积,在吸收经验模型和水沙模型的优点的基础上,建立了二者的耦合模型,模拟了部分开闸冲淤时闸下引河水沙运动.该模型与平面二维水沙模型相比简化了计算,且其计算精度满足工程应用的要求.通过计算比较多孔闸闸门全开及部分开闸的冲淤效果表明:对闸门上下水头差和闸内水量较小、闸下引河较短的情况,采取开启中孔闸的冲淤方式比多孔全开的冲淤效果好.

Under the effect of the tides at estuaries, deposition usually occurs in downstream area of the regulating gates which have the function of tide locks. This seriously affects the gate operation and management and may lead to disasters. So it is significant to predict the deposition and find an efficiency way to flush it. In this paper, the law of the deposition is studied and the amount of deposit is predicted. Absorbing the advantages of the empirical model and sediment model, a coupled model is developed to simulate the flushing process of partially sluicing and scouring. Compared with the 2-D sediment model , the coupled model is a short-cut calculation, and the accuracy of its results can satisfy the demands of engineering application. Through computation and comparison of the water flushing effect of fully and partially sluicing, we get the conclusion that when the water head between the upstream and downstream levels is low, the water storage is small, and the downstream river is short, it is more efficient to take the measure of partially sluicing than fully sluicing.