Abstract
Optimizing the structural form and array layout of breakwaters as the foundation of integrated systems is crucial for achieving deeper integration optimization and reducing the Levelised Cost of Electricity (LCOE) of wave energy converters (WECs). This study focuses on an integrated system combining a heaving WEC array with a multi-arc perforated breakwater. A three-dimensional analytical model based on linear potential flow theory was developed to resolve the hydrodynamic interactions among the system units and was validated using the wave energy conservation law. The analysis begins by evaluating the wave-concentrating performance and wave reflection of the multi-arc type breakwater, followed by a comparative study and a parametric study concerning array spacing and the unit number. The results indicate a strong positive correlation between the energy capture performance of each integrated system unit and the wave amplitudes within the corresponding wave-concentrating chamber. Compared to a WEC array deployed in front of a vertical breakwater, the proposed integrated system exhibits significantly superior wave energy capture performance at low frequencies, attributed to piston-mode resonance within the chambers, and demonstrates less sensitivity to variations in the wave incident angle. Furthermore, the system reduces the average wave amplitude in the waveward region by more than 15% and simultaneously lowers the horizontal wave forces acting on the WECs. Under perpendicular wave incidence, array effects enhance the energy capture performance, yielding a maximum mean interaction factor of 1.96. It is also shown that selecting a moderate inter-unit array spacing ensures a robust and balanced overall system performance.