Hydrodynamic performance investigation of the multi-degree of freedom oscillating-buoy wave energy converter

Wave energy is considered to be a kind of promising renewable energy due to its high energy density and enormous reserves. This study aims at examining the hydrodynamic performance of the multi-degree of freedom oscillating-buoy Wave Energy Converter (WEC). A three-dimensional numerical wave tank was developed using Star-CCM + software to investigate the interaction of waves with WEC. A mathematical model is built based on the structure of the multi-degree of freedom oscillating-buoy WEC. This paper investigated the variation in the device's energy conversion efficiency for different wave periods and spectral analyses of the motion of the floater. The effect of different elastic and damping coefficients on the device's performance was compared. The results demonstrate that the surge motion is the leading cause of the periodic variation in amplitude of floater motion. Heave motion is the main contributor to energy capture. Wave height has an influence on the contribution of the elastic and damping coefficients to the energy conversion efficiency.