Hydrodynamic performance characteristics of a curved-edged front lip wall oscillating water column (OWC) integrated with a pile-supported breakwater

A numerical wave tank based on OpenFOAM was employed to investigate the hydrodynamic performance of an oscillating water column (OWC) featuring a curved-edged front lip-wall and a curved bottom profile integrated with a pile-supported breakwater (PSB) exposed to regular waves. The effects of wave steepness ( H/L ) and relative water depth ( d/L ) on the key hydrodynamic parameters of the structure, OWC-PSB, including reflection, transmission, energy absorption, chamber oscillation, pressure characteristics, and energy extraction efficiency, were examined. The system exhibited enhanced energy absorption at higher d/L due to reduced reflection and transmission. The maximum energy conversion efficiency of 60 % was achieved at d/L = 0.4, for the lowest H/L tested. Lower d/L values resulted in a smaller phase difference between the chamber pneumatic pressure and the chamber water oscillation, thereby limiting pressure buildup and reducing efficiency. Increasing H/L decreased chamber water oscillation but slightly increased pneumatic pressure, resulting in an overall reduced efficiency. The influence of the occurrence of sloshing had a limited effect on the chamber efficiency, and negligible power loss was observed due to the smooth entrance configuration. It is found that the present integrated OWC–PSB system demonstrates a superior performance over conventional OWC-PSBs, offering simultaneous wave energy extraction and serving as a berthing facility for vessels. The findings provide valuable insights for the design and optimization of pile-supported OWCs under varying wave conditions.