Study On The Evolution Characteristics Of Crescent Waves In A Cylinder Diffraction

Crescent waves are special three-dimensional wave,the wave surface of crescent wave is composed of a horseshoe-shaped curved wave surface.crescent wave has three-dimensional strong nonlinearity,when the wave height has reached the limit wave height,the wave has broken or near broken,so it will have a greater destructive effect on the offshore structure.Because of its different waveform from the usual wave,it is of great practical significance to study the effect of crescent wave on the real ocean structure.This study analyzed the results of a physical model experiment of crescent wave in cylindrical diffraction.The spatial distribution and evolution of the wave field around the cylinder with Stokes wave and asymmetric perturbation under different water depth conditions are studied.The comparison of the two cases with and without cylinder shows that the existence of the cylinder is related to the horseshoe wave.The influence of the spatial distribution of the amplitudes of various order wave amplitudes gives the spatial distribution results of the maximum wave heights and amplitudes of various order waves around the cylinder in different water depths.The influence of water depth on the maximum wave height and amplitude of each order wave amplitude is discussed.By comparing the cylindrical and non-cylindrical conditions,we discuss the spatial evolution of the most unstable oscillation amplitude of the horseshoe wave along the direction of the wave propagation,and study the influence of the existence of the cylinder on the spatial evolution of the crescent wave.