Effects of WEC Geometry on the Performance of a WEC Array-VLFS Integrated System

Abstract This study focuses on analysing the effects of wave energy converter (WEC) geometry on the performance of an integrated system comprising a WEC array and a very large floating structure (VLFS). A numerical model of the integrated system is established based on multi-body potential theory, the discrete-module-beam (DMB) method, and the Lagrange multiplier technique. After validating the accuracy of the simulation approach, the present study examines the energy capture efficiency and hydroelastic response of the integrated system with various WEC geometry parameters, including length, width, draft, and shape. Owing to the complexity of the physical model of the integrated system, it is difficult to determine the optimal Power Take-Off (PTO) damping coefficient analytically. Therefore, a numerical search method is employed to obtain the PTO damping coefficients corresponding to different WEC geometry parameters. After a series of numerical simulations, the results reveal that, compared to the other three geometry parameters, the power output of the integrated system is more sensitive to the WEC length. Moreover, the incorporation of the WEC array leads to a significant reduction in the hydroelastic response of the VLFS. In addition, the draft and shape of the WEC exhibit limited influence on the structural response of the VLFS. All in all, the analytical methodology and framework presented in this paper can offer some insights for the design of similar integrated systems.