Numerical Analysis on the Motion Responses of Two-Body Point Absorber

Abstract

In recent years, various offshore devices ？ such as ocean monitoring and maritime defence systems ？ have been deployed in the outer sea. These devices require a consistent energy source to provide sufficient energy and should be clean to reduce carbon emissions. Wave energy satisfies these requirements and is getting attention. Among many wave energy converters (WECs), a point absorber type WEC is suitable for supplying low-demand power for these devices. This study is an initial phase of developing a point-absorber type WEC suitable for the Korean ocean environment. As this study is a preparatory step for the initial design, a potential-based frequency-domain motion analysis program is revised to capture the constrained motion between the two bodies. Model tests were also carried out for the Korean ocean environment to validate the developed numerical program. The numerical results agree well with the model test data for various operation conditions, validating the effectiveness of the developed numerical solver. Future research will focus on identifying optimal design parameters for real-sea applications using the proposed numerical method. Furthermore, the effects of various power take-off (PTO) systems on secondary and tertiary energy conversion efficiency will be investigated.