Abstract
Accurate assessment of Wave Energy Converters (WECs) performance requires a deep understanding of wave systems and energy distributions within both frequency and directional domains. This study introduces an innovative approach to evaluate the energy output of Multi-Body Floating Wave Energy Converters (MBFWECs) in complex sea states with multipeak wave spectra. The methodology involves developing a 2D Transfer Function (2D TF) to explore the power absorption capabilities of MBFWECs across specified wave frequency and directional ranges. To extend the approach to a real case, the waves measured at the northern coast of the Oman Sea are employed. Initially, hydrodynamic coefficients are determined using AQWA, and then, time-domain analyses are conducted using WEC-Sim, integrated with MATLAB-Simulink. Finally, to calculate the total extracted power, the derived 2D TF is multiplied by the Frequency-Directional Power Spectrum (FDPS) and the effective length of the device. A comparison between the results and those obtained through time history analysis confirms the accuracy of the introduced method. Furthermore, it is observed that neglecting the direction effect and assessing WEC power solely based on conventional approaches can lead to misleading information, particularly for sea states with multi-directional peaks (more than 20% error). Results reveal the importance of considering wave directionality in calculating the generated power. In addition, the wave energy of each direction can be absorbed efficiently by adjusting the draft in that direction separately. This innovative approach has significant implications for advancing wave energy conversion technologies and offers a practical approach to evaluating the real behavior of FWECs. In addition, it allows the optimal alignment of MBFWEC direction and geometries based on the FDPS of any region.