Ricerc@Sapienza

In this paper we propose a three-dimensional numerical study of the coastal currents produced by the wave motion in the area opposite the Cetraro harbour (Italy), during the most significant wave event for the coastal sediment transport. The aim of the present study is the characterization of the current patterns responsible for the siltation that affects the harbour entrance area and the assessment of a project solution designed to limit this phenomenon.

Irregular coastlines and variable bathymetry produce nonlinear effects on wave propagation which play a significant role on the formation of nearshore currents. To protect the coastline from the erosional action of nearshore currents, it is usual to adopt coastal defence works such as submerged breakwaters. If properly designed, they give rise to circulation patterns capable to induce sedimentation of suspended material at the nearshore region.

A three-dimensional numerical study of the hydrodynamic effect produced by a system of submerged breakwaters in a coastal area with a curvilinear shoreline is proposed. The three-dimensional model is based on an integral contravariant formulation of the Navier-Stokes equations in a time-dependent curvilinear coordinate system.

We propose a one-equation turbulence model based on a modified closure relation for the length scale of turbulence. The proposed model is able to adequately represent the energy dissipation due to the wave breaking and does not need any criterion to a priori locate the wave breaking point and the region in which the turbulence model has to be activated.

In this paper a new numerical model for the simulation of the wave breaking is proposed. In order to represent the complex geometry of coastal regions, the three-dimensional equations of motion are expressed in integral contravariant form and are solved on a curvilinear boundary conforming grid. A time-dependent transformation of the vertical coordinate that is a function of the oscillation of the turbulent wave boundary layer is proposed. New boundary condition bottom for the equations of motion expressed in contravariant form are proposed.

In this paper we propose a new numerical model for the simulation of the wave breaking. The three-dimensional equations of motion are expressed in integral contravariant form and are solved on a curvilinear boundary conforming grid that is able to represent the complex geometry of coastal regions. A time-dependent transformation of the vertical coordinate that is a function of the oscillation of the turbulent wave boundary layer is proposed. A new numerical scheme for the simulation of the resulting equations is proposed.