Capture performance of a square-shaped dual-chamber floating oscillating water column wave energy converter

The square-shaped dual-chamber floating oscillating water column (OWC) wave energy converter is designed to convert wave energy through the heave motion of its floating structure. This device uses airflow channeled from the dual chambers to drive a turbine generator, making it essential to investigate its primary energy conversion characteristics.

Numerical calculations and experimental tests were conducted to study the model's capture performance. Hydrodynamic software was used to simulate the response of the dual-chamber floating OWC wave energy model under different wave conditions. Regular wave experiments verified the accuracy of these simulations and evaluated the model's performance, while irregular wave experiments assessed its capture performance in real marine environments.

The numerical analysis indicated that the motion response of the dual-chamber wave energy model peaks near the heave natural period of the floating body, optimizing energy capture. It was also found that the angle between the incident wave direction and the model significantly affects performance. When the chambers are aligned front to back (0° angle), energy capture is maximized, suggesting this arrangement is the most effective. To verify the numerical calculations and assess the actual performance of the wave energy model, regular wave experiments were carried out. These experiments demonstrated that when the dual chambers of the floating OWC wave energy model are arranged front to back, the capture performance is superior compared to the left-right arrangement. The optimal capture performance periods for the front and back chambers of the model are not aligned, allowing the front-to-back chamber arrangement to broaden the range of optimal response periods, thereby enhancing the system's overall energy capture efficiency. Additionally, to evaluate the capture performance of the dual-chamber floating OWC wave energy model in real marine environments, irregular wave experiments were conducted. The experimental results showed a maximum capture width ratio of 41.84% under irregular wave conditions, which is close to 84% of its performance under regular waves. This indicates that the dual-chamber wave energy model maintains strong energy capture capability and stability even in challenging marine conditions.

Combining the results of numerical calculations and experimental tests, the dual-chamber floating OWC wave energy model exhibits excellent energy conversion performance across different wave conditions. The innovative front-to-back arrangement design of the dual chambers significantly enhances capture performance and broadens the range of optimal response periods. This research provides new ideas and methods for the development of wave energy conversion technology. The results have significant implications for optimizing and practically applying wave energy solutions, and they are expected to promote the development and utilization of marine renewable energy, thereby contributing positively to the advancement of green energy.