Numerical and experimental modeling of water wave interaction with rubble mound offshore porous breakwaters

摘要

In the present study, regular water wave interaction with rubble mound offshore breakwaters (RMOB) is investigated. The porosity of the RMOB is uniform, and the breakwaters are placed on the uniform seabed. Three different types of breakwaters such as (i) RMOB with still water level at the crest, (ii) emerged RMOB, and (iii) submerged RMOB are considered for the present analysis. The associated boundary value problem is handled for the solution using the boundary element method. Further, model tests are conducted, and the experimental results are compared with the numerical solutions. Quantitative analysis is carried out to show the effect of wave height and the height of RMOB's on the wave reflection, wave transmission, and wave energy dissipation. An emerged RMOB can effectively reduce the wave transmission compared to the submerged RMOB and RMOB with crest level at SWL (still water level). The results indicate that the minimum transmission coefficient ( 0.2) can be achieved in the short wave regime. This study also suggests that 90% incident wave energy can be dissipated by emerged RMOB with 46% porosity.