A study on motion and energy absorption characteristics of raft-type wave energy converter

This paper utilizes the method of adding a mass source and a damping term into the fluid governing equation for generating and absorbing the second order stokes wave. A nonlinear mathematic model for a raft-type wave energy converter with three floaters is proposed based on the Lagrange formulation. A number of simulations are accomplished in CFD software by numerically solving the non-linear mathematical model for investigating the motion and energy absorption characteristics of the raft-type wave energy converter. The simulation results show that the increasing of the hydraulic damping can decrease the root-mean-square angular velocity of the floater and increase the hydraulic moment. This indicates that there exists an optimal hydraulic damping for maximizing the absorbed energy.