Research On Numerical Model For Waves In Coastal Region Based On Boussinesq Equations

Wave deformation and wave-induced current has been an important topic in coastal dynamics. A comprehensive numerical model for wave deformation and wave breaking plays an important role not only in practical application but also in theoretical research. This paper summarized various Boussinesq-type wave-breaking models and analyzed some problems related to the application to the wave-induced current. In this thesis, first a full nonlinear Boussinesq wave model is established to simulate wave deformation in coastal area. The model is applied to wave breaking on plane sloping beach. The numerical results of Wei model and Nwogu model are compared with linear solutions and Shuto nonlinear solutions.This paper proposed an improved wave-breaking model based on the fully nonlinear Boussinesq equations to simulate wave breaking in the surf zone. The model employs the concept of surface roller to determine the production term in the equation and thus the eddy viscosity in the Boussinesq equations can be calculated. One of the difficult points in simulating wave run-up is the numerical treatment of the moving shoreline. In the present work we take slot technique. The model is verified by experimental data in terms of wave height and set-up and set-down. Comparison with measurements shows a satisfactory agreement. Also, the processes of the transformation of wave energy into turbulent energy,the dissipation and transport of turbulent energy by convection and diffusion are discussed.