Diffraction of Multi-directional Random Waves Asymmetric in Direction

Abstract

In deep water, when multi-directional random waves symmetric to the direction of propagation are incident obliquely on the shore, directional asymmetry is generated as a result of refraction. In this research, considering directional properties of asymmetry caused by refraction, we calculated refraction pattern of multi-directional random waves near a semi-infinite breakwater and a breakwater gap, and compared it to the results of unidirectional random waves and of monochromatic wave. When angle of incidence of the wave on a semi-infinite breakwater is less than 90 degrees, wave height was calculated to be greater when a asymmetry was considered compared to the case of perfect symmetry; and the opposite was evident when the angle of incidence was greater than 90 degrees. In case of a breakwater gap, near the perpendicular direction to the entrance, wave height distribution was found to be more concentrated when asymmetry was considered compared to when it was not.