CFD-based investigation of optimal design parameters for a raft-type wave energy converter

The performance of two-body hinged raft-type Wave Energy Converters (WECs) depends on their dynamic response to varying ocean waves. This study employs Computational Fluid Dynamics (CFD) simulations, involving nonlinear wave-structure interactions, to investigate the optimum device parameters for maximizing the performance in case of different wave conditions. A series of model-scale simulations explore how variations in mass, center of mass, and geometry of a water insulator skirt affect absorbed power and capture width ratio (CWR). Results demonstrate that tuning the natural frequency of the WEC to align with the incident wave frequency—by adjusting skirt height and mass—can enhance absorbed power by up to 10% in certain conditions. This tuning can be achieved through simultaneous, adaptive adjustments of skirt height and mass. However, natural frequency matching alone is insufficient. Suboptimal energy capture may still occur due to unfavorable barge trim, particularly for the front barge. Ensuring proper trim in hydrostatic equilibrium is therefore essential to maximize energy extraction. These findings provide valuable design insights to improve CWR and reduce the levelized cost of energy (LCOE) for hinged raft-type WECs.