Modelling of the wave propagation, the coastal currents and the induced topographic changes

This paper models the sea bottom evolution. This model is built up on three main parts. The first one describes the wave propagation, taking simultaneously into account the refraction, the diffraction and the reflection but also the energy dissipation caused by wave breaking. This model is solved by the numerical method of the finite volumes, using an iterative resolution (the GMRES method). Several validations of this model have been carried out on many examples such as harbors of various geometries and depths, beaches,… The wave induced currents are computed in the second part based on the concept of the radiation stresses describing the excess of the flux momentum caused by the waves. A model based on the complete Navier-Stokes equations integrated on the depth and associated with appropriated forcing and friction terms is used. This model is computed as an update of WOLF software (HACH, ULg) and is applied to some examples such as beaches with or without coastal structures. Finally, the third part is about the sediment transport. It exhibits the topographic modifications of the coastal sea bottom caused by the waves and their currents. A loop execution of these three models ends this work. It gives us an operational tool to describe the topographic evolution of the coastal areas caused by the incident waves, the induced currents and then the resulting sediment transport, fulfilling the objectives of this paper.