Wave Transformation on Wave Catcher Shore Protection – Dual Slope (WCSP-DS) Zig-Zag Model with Wave Focused Wall

Abstract

Abstract The Wave Catcher Shore Protection Dual Slope (WCSP-DS) is a coastal structure with a dual function of shore protection and wave power generation. The WCSP-DS structure captures seawater through overtopping into the crest reservoir resulting in a higher reservoir water level than the sea. This elevation difference will be the pressure height (head) and is represented by the freeboard height (Fb) and together with the overtopping discharge unit (q) will be the main parameter for electrical power. This study aims to increase the discharge value (q) at the maximum freeboard height (Fb) through engineering effort in the wave transformation process by adjusting the setting position of the WCSP in a zig-zag manner and adding a wave-focused wall (WFW) to produce a maximum deformed wave height (Hdf) in front of the WCSP-DS. Located in Hasanuddin University’s Coastal & Environmental Engineering Laboratory, the study was carried out experimentally using geometrically scaled 1:20 physical model simulations. Three Dimensional (3D) wave basins in the size of 10 m x 15 m x 1 m equipped with an automatic wave generator and data recording instrument were utilized. Two type models namely the M1 (without collector) and the M2 (with collector) were simulated with relative water depth (d/z), freeboard height (Fb), incoming wave height, and period (Hi & T). The results indicated that the deformed wave height (Hdf) increased significantly ranging from 300% to 900% on M1 and from 350% to 1100% on M2. The increase in the value of Hdf also increases the discharge (q) that enters the reservoir. By these results, a combination of Fb and q can be selected which can generate optimal electrical power.