A SEMIIMPLICIT 3-DIMENSIONAL HYDRODYNAMIC MODEL INCORPORATING THE INFLUENCE OF FLOW-DEPENDENT EDDY VISCOSITY, BOTTOM TOPOGRAPHY AND WAVE-CURRENT INTERACTION

A semi-implicit finite difference three-dimensional hydrodynamic model taking into account the effects of wave-current interaction through t he bottom boundary layer and the influence of flow-dependent eddy visc osity and bottom topography is developed. The sigma-coordinate system in the vertical direction is introduced for the accurate definition of the bed and surface boundary conditions. The effectiveness of the mod el is verified by comparing the computed circulation in an idealized e stuary with that by others. Application of the model to the northern S outh China Sea is also carried out for the hindcasting of a storm surg e event. It is found that the inclusion of constant wave effects in th e hydrodynamic model cannot improve the prediction of surge levels. A wind wave model should be used in conjunction with the hydrodynamic mo del if prediction is to be improved. (C) 1997 Elsevier Science Limited .