Experimental determination of the performance characteristics of an undulating submerged obstacle

Abstract

This study reports physical experiments conducted with various combinations of undulating breakwaters under various wave conditions. The preliminary analysis consists of wave attenuation characteristics and efficiency of various combinations of sinusoidal breakwaters estimated by the transmittance, the variation in reflectance and loss coefficient, and the optimisations of a variety of sinusoidal breakwaters. The interaction of surface waves scattered by undulating ocean floor topography, such as sinusoidal bars, is of fundamental importance to sediment transportation. Thus, this study investigates the characteristics of multi-array impermeable sinusoidal submerged breakwaters experimentally. The interaction between waves and the obstacles are also investigated using the reflection coefficient, transmitted coefficient, and attenuation of wave energy. Most of the related investigations conducted theoretically and experimentally for the predictions of the propagation of water waves over the undulating ocean floor topography have focused on the problems of Bragg resonance. Specific parameters could be suitably chosen to control the resonance; composite artificial obstacles with specific parameters, which reduced the intensity of transmitted waves, may be used to protect beaches. Therefore, this study discusses the properties of the reflection coefficient of the sinusoidal breakwaters, the attenuation caused by the varying combinations of submerged obstacles, the effectiveness of wave attenuation, and the optimisation of the disposition of sinusoidal breakwaters.