SPH modeling and experimental validation on power performance and dynamic response of a novel swing-wing wave energy converter

Considering the problems of limited endurance and small working radius brought by traditional battery-powered marine unmanned vehicles. A concept of swing-wing wave energy converter (SW-WEC) is proposed to efficiently convert wave energy into mechanical energy and subsequently into electricity. Accurately analyzing the dynamic response of SW-WEC is crucial for predicting power performance but is challenging with traditional numerical methods. This paper establishes a fluid-structure coupling dynamic model of a full-size SW-WEC by combining the smoothed particle hydrodynamics (SPH) method and Chrono-Engine. The study focuses on evaluating the accuracy of SPH method in predicting dynamic response and power performance of the SW-WEC, both experimental and numerical studies are conducted to investigate SW-WEC's interaction with waves. The SPH numerical model can accurately simulate the motion response of SW-WEC under wave action and shows good agreement with experimental results. This result shows the potential of SPH method in simulating large motion of such three-body wave energy devices, although it is computationally heavy. Furthermore, we investigate the influence of wave height, period, and Power Take-Off (PTO) damping on power performance. The results indicate that power performance improves as wave height increases but diminishes as wave period increases. The maximum generating power of SW-WEC exceeding 12 W, and the maximum capture width ratio (CWR) surpassing 0.08. There is an optimal PTO damping for achieving the best power performance, which varies under different wave conditions. This work provides a novel and effective modeling and analysis method for the SW-WEC and offers guidance for its structural optimization.