Numerical Simulation of the Decay Motion of a Water Column for the Oscillating Water Column Type Wave Energy Converter Using the Particle Method

Abstract The floating oscillating water column-type wave energy converter (OWC-WEC) is highly maintainable and safe because it has no moving parts under water. Estimation of water column’s motion in the air chamber is required to develop a high-performance floating OWC-WEC. The traditional approach is to model the system as an equivalent rigid body. The final goal of the present study is to reveal the details of the motion mechanism as fluid by Computational Fluid Dynamics (CFD). In this study, a high-accuracy two-phase flow moving particle simulation method was developed by combining existing and unique models to improve unstable numerical oscillations. Numerical simulations and water tank experiments were conducted for a free-motion test of the water column to validate the proposed method and analyze the fundamental motion of the water column in the air chamber of a floating OWC-WEC. A comparison between the calculated and experimental results showed that the proposed method developed reliably replicated the phenomena, although the three-dimensional effect was important, and the fundamental applicability of the method was clearly demonstrated.