Hydrodynamic and power conversion performance of a novel dual-chamber OWC floating breakwater

Integrating wave energy converters with floating breakwaters can reduce the cost of wave-energy utilization. This study proposes a dual-chamber oscillating water column floating breakwater (OWC-FB) and investigates its hydrodynamic performance and energy-capture performance through physical model tests. The model is a parameterized fundamental-research model, without a prescribed engineering prototype or unique geometric scale ratio, and is tested only under normally incident regular waves. The effects of relative chamber opening width, top opening ratio, and wave height on wave attenuation, motion, mooring loads, and energy capture are examined. Within the parameter ranges of the present and reference models, the OWC-FB exhibits lower reported long-wave transmission and higher capture width ratios over part of the compared range, demonstrating long-wave attenuation and broadband energy-capture potential. A relative chamber opening width of b/S = 0.596 reduces long-wave surge and wave-side mooring-force peaks while increasing total CWR. The top opening ratio regulates chamber airtightness and equivalent pneumatic damping; α = 0.87% produces the highest CWR. Wave-height effects are frequency dependent: larger waves increase short-wave dissipation, weaken long-wave attenuation through stronger motion, and increase mooring tension. Within the parameter range of the present study, the combination of b/S = 0.596 and α = 0.87% is recommended.