Hydrodynamic performance of hybrid floating breakwater integrated with oscillating water column

Abstract

The present study investigates the hydrodynamic performance of different types of hybrid floating breakwaters (HFB) integrated with an oscillating water column (OWC). The study is performed for five different cross-sectional shapes of HFB, such as rectangular, box, H, ?, and trapezoidal, with the inclusion of OWC of the same dimension in all of the hybrid floating breakwaters. The performance of the HFBs is examined for its motion response, wave transmission coefficient, and power capture under the action of the regular waves, considering the incident wave normal to the structure. The motion response and wave transmission characteristics assessment are based on potential flow theory, and the power capture due to the HFB is assessed using the volume of fluid (VOF) flow computation method. The HFB model performing better in terms of transmission coefficient and power capture considering wider bandwidth for the considered surface gravity wave frequencies is selected to investigate the effect of changes in HFB’s parameters, such as length, width, draft, and wave incident angle on the hydrodynamic performance. Additionally, the streamline contours for the air flow velocity variation through the OWC chamber in different types of hybrid floating structures are analysed for better understanding of flow through visualisation. The aforementioned streamline contour is determined for the wave frequency where the maximum wave energy capture in the HFB models is observed. The study will facilitate the researchers to comprehensively investigate the stability of hybrid floating breakwater under the influence of regular waves with the help of the findings of the present investigation. © IMechE 2025