Experimental and Numerical Study of Wave-breaking on Reef Flat
Coral reefs have the functions of dissipating wave energy and protecting the coastline,which have very important ecological and economic values.An in-depth understanding of distribution patterns of wave energy dissipation due to wave-breaking on reef flat is critical for the analysis of sediment transport and the response of coastal structures in shore-reef topography.In this study,wave-breaking on the shore-reef topography experiments are conducted in a wave flume to examine the effects of submerged depth of reef flat,incident wave height and spectral peak period on wave and wave-setup evolution.A phase-averaged numerical model based on energy conservation is employed to simulate wave heights and wave-setup,and the calculated data are used to analyze the relationship between the distribution of wave energy dissipation due to wave-breaking and incident wave elements and submerged depth of reef flat.The results indicate that wave heights tend to stabilize on the reef flat after breaking violently near the reef edge,and the stable wave heights(wave-setup)correlate positively(negatively)with submerged depth of reef flat.The numerical model accurately predicted wave heights and wave-setup along the coral reef,and the Root Mean Square Errors are 0.0033 m and 0.0013 m respectively.A dimensionless parameter,wave entropy,is introduced to characterize the uniformity of the distribution of wave energy dissipation,and it is found that within a certain range,the uniformity of the distribution of the wave energy dissipation due to wave-breaking is positively correlated with the submerged depth of reef flat and the incident wave period,and negatively correlated with the wave height.Taking incident wave elements and submerged depth of reef flat into account in this paper,then a parameterized formula to predict wave entropy is proposed,and the square of correlated coefficient is 0.85.
Coral reefsWave breakingWave energy dissipationWave entropy
万方数据
维普
