DAMPING OF SURFACEWAVES PROPAGATING OVER A MUD BED

• Main Author: Mauditra Aulia Matin, Alvedian
• Format: Final Project
• Language: Indonesia
• Online Access: https://digilib.itb.ac.id/gdl/view/55141
• Institution: Institut Teknologi Bandung

Tall ocean waves erode shores and damage manmade structures. Mangrove forests, which often grow on muddy coasts, can mitigate these harms by reducing wave heights. Existing studies in the literature focus on mud-water interactions or water wave interactions with submerged vegetation but not do not investigate the overall effect of both. This analytical and numerical study investigates the combined effects of mud and vegetation on wave height. A model based on the linearized shallow water equations is formulated to describe wave motion over two incompressible fluid layers. The wave’s dispersion relation is derived for two lower fluid layer types: inviscid and viscous. A numerical scheme is constructed using a finite volume method on a staggered grid. Wave attenuation due to the presence of a lower fluid layer is measured using numerical simulations based on the aforementioned scheme. Results are validated by comparing numerical results to wave height reduction values obtained from the analytical solution. The model is then extended to take into account the presence of a vegetation patch (porous medium) by adding a friction term. Using the same finite volume method, a numerical scheme is constructed and simulations are run to obtain wave height reduction values. The results are used to analyze the effectiveness of mangrove forests in coasts possessing mud banks as coastal defense structures.