The 12th International Conference on Hydrodynamics
18 – 23 september 2016, Egmond aan Zee, The Netherlands
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NUMERICAL MODELLING OF COASTAL PROTECTION BY CORAL REEF USING A CFD MODEL


Go-down ichd2016 Tracking Number 146

Presentation:
Session: Theoretical Hydro & Environmental Hydro
Room: Room 2
Session start: 10:30 Thu 22 Sep 2016

Inigo Losada   losadai@unican.es
Affifliation: IH Cantabria - Universidad de Cantabria

Javier Lara   lopezjav@unican.es
Affifliation: IH Cantabria - Universidad de Cantabria

Maria Maza   mazame@unican.es
Affifliation: IH Cantabria - Universidad de Cantabria

Pelayo Menendez   pelayo.menendez@unican.es
Affifliation: IH Cantabria - Universidad de Cantabria


Topics: - Hydrodynamics in ocean, coastal and estuary engineering, - Environmental hydrodynamics

Abstract:

One of the most relevant features linked to coastal hazards assessment is the increment of mean water level due to broken waves, called wave setup. In fringing reefs, wave set-up is enhanced inducing larger run-up at the beach. Despite the well known hydrodynamic processes occurring in natural sandy beaches, the role played by bottom vegetation in fringing reefs is very relevant and poorly understood. Although many solutions are used to protect the coast, including artificial man-made structures or natural solutions based on coral reefs or vegetated bottoms, their influence in reducing wave energy needs further analysis. A comparative analysis of different scenarios, such as natural reefs, man-made submerged rubble-mound breakwaters and vegetated reefs, is performed in this work with the aim of demonstrating the ability of vegetated reefs to reduce wave energy at the coastline. The coral reef geometry located in Playa del Carmen (Mexico) has been used as a case study. Single transient wave groups have been analysed. The model called IH2VOF, a Navier-Stokes solver, is used. Results have shown that wave setup and wave run-up are mainly influenced by wave breaking. It has been observed that the more relevant reduction on wave setup and wave run-up is observed when a fore reef is not present. The presence of a vegetated reef has been revealed as an efficient solution, especially for the largest wave height cases, decreasing the wave run-up at the beach.