Keywords
wave statistics
freak waves
wavelet transform
How to Cite
Abstract
A series of physical experiments on the variations of statistics of random waves propagating over a submerged bar were conducted. Random waves were generated by JONWSAP spectra, varying initial spectral width but fixing the wave height and peak frequency. It is found that some freak waves can be formed in the shoaling region close to the top of the bar. And the appearance of these freak waves are mainly caused by the local triad wave-wave interactions. In addition, the probability occurrence of the freak waves has negligible relation with the spectral width. Additionally, the appearance of freak waves is relating to the increasing of wave groupiness in the shoaling region. Furthermore, the relationship between the skewness and kurtosis in the shoaling region can be predicted well with the formula by Mori and Kobayashi (1998).References
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