Hydroelasticity and power capture of raft-type WEC–interconnected VLFS configuration

This paper presents a systematic numerical investigation of the hydroelastic response and energy capture characteristics of raft-type WEC–interconnected very large floating structure (VLFS) system. In the proposed configuration, the WEC is positioned at the fore-end of VLFS, and its power take-off (PTO) mechanism is modeled as a hinge with rotational damping. The wave excitation induces the rotational motion around the hinge, which can drive the PTO to absorb the wave energy. Meanwhile, adjacent VLFS modules are connected by hinges with prescribed rotational stiffness, enabling inter-module rotations and thereby representing the global structural flexibility. From a methodological perspective, the VLFS structure is discretized employing the discrete-module–beam bending (DMBB) method, and the motion equation of the system in the frequency domain is formulated with Lagrange multiplier method. A numerical search procedure is further implemented to determine the optimal PTO damping, with the objective of maximizing power capture efficiency. On this basis, a parametric study is utilized to evaluate the influence of wave and system properties. The results demonstrate that variations in wave and system parameters can significantly influence both the deformation of the VLFS and the power capture of the WEC. Overall, the present study provides valuable insights for the structural design and performance optimization of WEC–VLFS systems.