Nonlinear regular wave, submerged breakwater and seabed dynamic interaction

Abstract

Numerical and physical models have been developed to study the nonlinear dynamic interaction between water waves and permeable submerged breakwater over a finite thickness sand seabed. Modified Navier–Stokes equations have been used to solve the flow inside the porous media, and Biot's equations have been applied to solve the poro-elastic media. A combined BEM–FEM model has been modified to simulate the flow inside the porous media and the wave deformation outside it. A poro-elastic finite element model has also been adapted and utilized under the effect of the nonlinear wave pressure, computed by the BEM–FEM model, along the surface boundary. A physical model has been made to record the water surface levels around the breakwater and the dynamic pore–water pressure inside the breakwater and foundation. The BEM–FEM model reproduces the experimental results in the wave field fairly well. The pore–water pressures computed by the poro-elastic and BEM–FEM models are compared with the experiment. The influence of the breakwater size on the wave deformation and the effect of the seabed thickness and stiffness on the breakwater stability are examined.