Parametric study of solitary wave propagation and runup over fringing reefs based on a Boussinesq wave model

Abstract

In this paper, a fully nonlinear Boussinesq wave model FUNWAVE-TVD is applied to study solitary wave propagation and runup over fringing reefs. Validation with newly performed laboratory experiments indicates that the wave motions over the forereef slope and reef flat and the runup/rundown process on the backreef slope are reasonably reproduced by the present model with a calibrated bottom friction coefficient for both non-breaking and breaking solitary waves. Sensitive analysis of grid size reveals that the grid spacing is important in capturing the runup height accurately in this study. Predicted spatial distributions of maximum surface elevations from the validation cases also show that compared with the plane beach without fringing reefs, bore propagation processes induced by the wave breaking over reef bathymetry are important in decay of solitary wave and consequent runup height. To comprehensively understand the solitary wave propagation and runup processes over fringing reefs, a parametric study was carried out to analyze the wave–reef interactions under various conditions through a series of numerical experiments. The effects of different hydrodynamic and reef morphological parameters, including the incident wave height, water depth over the reef flat, forereef slope angle and backreef slope angle, on the wave runup were mainly focused on and investigated in this study.