Author(s): Mohammad Kazem Sharifian, Yousef Hassanzadeh
Linked Author(s): Mohammad Kazem Sharifian
Keywords: Bragg reflection, submerged breakwaters, reflection coefficient, transmission coefficient, coastline protection
Abstract: Breakwaters submerged in the sea have the merits of not affecting coastal environment and allowing water circulation and fish passage. Thus, the submerged breakwaters are often used for providing partial sheltering to coastlines and coastal structures. Semi-circular breakwaters have major merits from the hydrodynamic viewpoint. Nevertheless, there has been little research about these kinds of breakwaters and their engineering performance in wave energy reflection. In this study, characteristics of the Bragg reflection due to multiple semi-circular submerged breakwaters are investigated by 2DV numerical modeling based on Reynolds Averaged Navier-Stokes (RANS) equations. The results show that, high Bragg reflections can be achieved by increasing the number of the breakwaters. The investigation of velocity and turbulent kinetic energy contours show that velocities become larger at the upper side of submerged bars and decrease at the back side which is due to the fact that significant amounts of the incident wave energy is reflected by the Bragg reflection effects. Also, the study of flow physics shows that the amounts of vorticity and vortex generation are very low in case of semi-circular submerged breakwaters
Year: 2017