Wave propagation over coral reef–lagoon topography based on porous medium model.

This article presents a numerical model based on the Reynolds-averaged Navier–Stokes (RANS) equations to simulate wave propagation and breaking over porous coral reef topography, focusing on both regular and irregular waves. The model incorporates a porous media approach to realistically represent coral reef surfaces, accounting for porosity and permeability effects on wave deformation, energy dissipation, and water setup in reef flats and lagoons. Validation against physical experiments demonstrates the model’s accuracy in capturing wave behavior, including the influence of wave height, period, inundation depth, and reef porosity on wave transmission and water level changes. Key findings indicate that larger wave heights and periods increase energy dissipation and water setup, higher porosity reduces transmitted wave height due to frictional losses, and lower water levels enhance wave reflection and energy dissipation in lagoons. These results provide refined hydrodynamic insights relevant for coastal engineering and ecological management in coral reef environments.