Low-Crested Structures: Boussinesq Modeling of Waves Propagation: Fid-Bau Portal

Low-Crested Structures: Boussinesq Modeling of Waves Propagation

Prinos, P. / Avgeris, I. / Karambas, Th.

Abstract In the last few decades, low-crested structures have been extensively used in costal zones for shoreline protection and to prevent beach erosion. Their presence results primarily in wave energy dissipation through the physical mechanisms of wave breaking and friction. In most of the cases these structures are rubble mound permeable breakwaters whose design is based on empirical rules. In this study wave evolution over porous submerged breakwaters is investigated with the use of a 2DH-Boussinesq-type model, following a procedure similar to that of Cruz et al. (1997). A higher-order Boussinesq-type model, with improved linear dispersion characteristics is used to describe wave motion in the regions upstream and downstream of the breakwater (Karambas and Koutitas, (2002)). In the region of the breakwater, the model is used in conjunction with a depth-averaged Darcy-Forchheimer (momentum) model describing the flow inside the porous medium. Above the breakwater the model incorporates two extra terms accounting for the interaction between the waves over the structure and the flow within the porous structure, one in the continuity equation and one in the momentum equation respectively. Computed results are compared with experimental measurements in a wave flume and a wave basin, provided by Vidal et al. (2002) and Zanuttigh and Lamberti (2003) respectively, as part of a research carried out for the European Research project DELOS-(http://www.delos.unibo.it).