Experimental Study On The Character Of Wave Propagation On Coral Reef Terrain

When propagating from the deep sea to the water area near the coral reef,a series of complex nonlinear changes will occur.To simulate the propagation and evolution process of waves around reefs,the sea area around an island reef in China was chosen as the research object in this paper.A two-dimensional reef terrain model?1:50?was set up in the wave test flume,and many wave gauges were srt around the reef profile for recording the wave parameters.Based on the marine environment data of the actual sea area,28 regular wave conditions and 29 irregular wave conditions have been established spectrally in this experiment.The internationally recognized Goda improved JONSWAP spectrum was selected as the input of irregular wave,and the wave spectrum peak elevation factor was 3.3.By adopting the statistical analysis method,wave evolution process was analyzed,which including changes in wave form,wave parameters,such as wave height and wave period.In the surf zone,the positions of wave breaking and wave energy dispassion after breaking were also discussed.Meanwhile,wave spectrum curves were drawn by spectrum analysis method.By comparing the curves of different investigating points,we studied the spectrum changes,wave energy transformation and the multiple times secondary spectrum evolution.The mean water level would rise or drop after wave breaks,in order to well estimate the water level of the sea area around our target island.The wave set-up induced by wave breaking was also discovered in experiment,and it would have great impact on mean water level,which the maximum ???/H₀ of regular wave cases could reach 23.15%and that of irregular wave cases could reach16.94%.Detailed studies were conducted on the importance of incident wave height,period and water depth to wave set-up.