Experimental and Numerical Modelling of WEC for a Fishing Buoy

Fishing buoys are confronted with the problems of insufficient power supply and loss. To address these challenges, a small innovative fishing buoy equipped with an internal pendulum and powered by wave energy is designed. Its structural shape enables it to maintain a stable surfing state, thereby facilitating more efficient wave energy capture. Free decay tests and wave energy capture tests were conducted via numerical and experimental simulations. A mathematical model was proposed and validated using experimental data. Through free decay tests, the natural periods of the device in heave and pitch motions were obtained, which ranged from 1.0 to 1.42 s. The results of the wave energy capture tests indicate that the device can capture approximately 300 mW of electrical power under small-wave conditions. Additionally, the mechanical damping coefficient of the buoy-pendulum system was estimated to be 0.15 Nms/rad, and the mechanical efficiency of the wave energy converter was 15%. Preliminary optimization was carried out through numerical model simulation, which is conducive to the refined design of the device. This study provides a reference for the development and design of similar wave energy conversion devices.