波浪、潮流和风暴潮耦合模式及悬沙输移规律的研究

近年来，由于河口、海岸地区的泥沙运动与港口、航道以及海岸的冲淤有着直接的关系，对一些海岸建筑物比如防波堤、护岸工程等造成一定的威胁，甚至于使其完全丧失使用价值，造成巨大的损失。为此人们越来越重视对这一问题的研究。本文为估计岸滩的冲淤变化和了解岸滩的演变规律，对影响泥沙运动的海洋动力要素进行了研究。为研究悬沙的输移规律，建立了一个由两部分组成的二维悬沙模型系统：①水动力模式。建立了一个综合多因素的二维波浪、潮汐和风暴潮耦合模式，以此来研究波、潮、风暴潮间的相互作用，并为泥沙计算提供流速场。②二维悬沙模式。运用得出的流场来研究悬沙的输移扩散规律。其中所采用的波浪模式是将流对波浪场的影响同时加以考虑的耦合数学模型，将流速加入波能方程，并考虑由于水面的升降而产生的不定常水深对波浪场的影响，再将波浪场对流场的影响通过辐射应力、考虑波浪影响的底应力以及依赖波龄的表面风应力耦合到流场中，从而建立了一个综合多种因素的波浪、潮汐、风暴潮联合作用下的二维悬沙模型系统。并在此模型系统的基础上，对黄河口泥沙的输移问题作了探讨，为今后的防堤、护岸工程提供依据。

A WAVE-TIDE-SURGE INTERACTION NUMERICAL MODEL AND ITS APPLICATION IN THE STUDY OF SUSPENDED SEDIMENT TRANSPORT

A numerical model is applied here to simulate the transport of SS (suspended sediment). The whole model mainly consists of two parts:One is the hydrodynamic model, the synchronous coupling of a modified second-generation wave model and a two-dimensional tide-storm-surge mode, which provides the wave factors, 2-D current velocity and the sea surface elevation, and is used to study the interaction of waves, current, and storm surge. Storm-induced currents clearly affect the wave characteristics especially the wave height.The other is the SSC model, which uses the current data acquired from the above model to drive the movement of the SS, to simulate the distribution of SS. In the period of strong wind and surge, the SSC varies much more than that driven by pure tidal currents, especially in the coastal zone, where wave also plays an important role in the process of SS transport, and can increase the SS greatly.Here we apply this model system to simulate the transport of the SS discharged from the Yellow river. The results showed that: the high SSC area is around the Yellow River Mouth. There are two branches of SPM from the Yellow River. One goes into the Bohai Gulf along its southern coast, while the other into the Laizhou Gulf and then transports out of the Bohai Sea through the Bohai Strait.