An Integrated Model For River, Estuarine, And Coastal Hydrodynamics

An integrated model for the study of river, estuarine, and coastal hydrodynamics is developed. The model consists of a two-dimensional component for coastal hydrodynamics and a one-dimensional component for river channel flows.The two-dimensional model for coastal hydrodynamics is based on the extended Boussinesq equations. A simple but effective model is introduced to represent the energy dissipation due to wave breaking and seabed friction. The model is applied to the computation of wave transformation and breaking over a submerged shoal, and of wave transformation around a detached breakwater. In both cases, the computational results are in good agreement with experimental data. The model is also shown to be valid for wave-induced currents. The excellent performance of the model is demonstrated as applied to the simulation of the rip current generated by waves propagating over a plane beach with two longshore bars separated by a narrow channel.The Saint-Venant equations are used as the governing equations of river hydrodynamics. They are also solved by the finite difference method. The model is verified by an analytic solution for the propagation and collision of solitary waves. It is also used to the computation of the tidal bore in Qiantang River, and the computational results are shown to agree well with measured data.The integrated model is used to study the interaction between the river flow and the tidal flow in the estuary of Yangtze River. The computational results are demonstrated to be in good agreement with the measured data.