Optimization of two configurations of a two-buoy wave energy converter

This study proposes an efficient optimization framework that integrates an analytical frequency-domain model with the Response Surface Methodology (RSM) to determine the optimal geometric configuration of a floating two-buoy wave energy converter (WEC). Within this framework, RSM is employed to establish a surrogate model that captures the relationship between input geometric parameters and the corresponding energy output through regression analysis. A novel optimization objective is introduced in the form of the capture width ratio divided by the mass ratio, which we call the 'capture width ratio (CWR)-to-mass ratio', aiming to maximize energy capture while simultaneously minimizing structural cost. Two distinct two-buoy configurations are examined: one in which the inner buoy is connected to a submerged body, and another in which the inner buoy is fitted with a damping plate. The effectiveness of each design is evaluated via sensitivity analysis with respect to key geometric parameters. Furthermore, the frequency-dependent adaptability of the optimal geometric parameters is assessed to identify the most optimal inner buoy configuration. Results demonstrate that the proposed RSM-based predictive model offers a computationally efficient and adaptable mathematical framework. The incorporation of cost considerations into the optimization objective enhances the practical feasibility and deployment potential of the two-buoy WEC system in real-world marine environments.