THE WAVE FIELD BEFORE A U-OWC BREAKWATER

In this work, we carried out a numerical experiment aiming to analyse the interaction between waves and a U-OWC breakwater. Amplitude and phase of waves acting on the outer opening of this plant are essential to determine the energy absorption. The method adopted to study the wave-plant interaction is the numerical experiment carried out through the integration of Reynolds averaged Navier-Stokes equation (RANS). The water-air interaction is taken into account by means of the Volume Of Fluid (VOF) model implemented in the commercial CFD code Ansys Fluent.To validate the numerical wave flume, we carried out some preliminary tests finalized to compare numerical results of a vertical reflecting wall with the analytical solution of linear standing waves. The results have shown that there is a suitable correspondence between analytical and numerical simulation and this confirms that the wave field expanding along the wave flume has the characteristics of a progressive wave.The numerical experiment has been carried out by substituting the reflecting vertical wall with the U-OWC. The geometry and size of the U-OWC breakwater utilized in this work is the same as the 1:6 scale physical model of breakwater tested directly at sea by [1], in the Southern coast of Italy. To check the plant working conditions, we made several simulations, varying the wave period. Finally, we compared the numerical results with the experimental data