Analysis of wave overtopping on an impermeable coastal structure using a RANS-VOF numerical model

Abstract

The global warming is responsible for increasing the sea level and, consequently, can cause overtopping on coastal structures. The prediction of this phenomenon is difficult because involves turbulence, wave breaking and run-up. The objective of this study is to analyze numerically the wave overtopping on coastal structures by using the FLUENT® numerical model, which is based on Reynolds-Averaged Navier-Stokes equations (RANS) and uses the Volume of Fluid method (VoF) to track the interface between water and air. Influences of mesh size, turbulence model (k- and k- SST) and bottom condition (slip and no-slip) are investigated in a flume with an impermeable breakwater at its end. Two cases with different heights of incident regular waves are tested. In general, the free surface elevations up to the breakwater obtained by different conditions are very similar for both incident waves. However, the overtopping volumes have shown more important differences.