Journal of Ocean Engineering and Technology (한국해양공학회지)

Korean Society of Ocean Engineers (한국해양공학회)
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Numerical Analysis for Motion Response of Modular Floating Island in Waves

  • Hyo-Jin Park (Department of Naval Architecture and Ocean Engineering, Seoul National University) ;
  • Jeong-Seok Kim (Eco-friendly Ocean Development Research Division, Korea Research Institute of Ships & Ocean Engineering) ;
  • Bo Woo Nam (Department of Naval Architecture and Ocean Engineering, Seoul National University)
  • Received : 2022.09.26
  • Accepted : 2022.12.01
  • Published : 2023.02.28
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Abstract

In recent years, modular-type floating islands have been considered as a promising option for future ocean space utilization. A modular floating island consists of a number of standardized pontoon-type modules and connectors between them. In this study, the motion responses of a modular floating island in waves was investigated based on frequency-domain numerical analysis. The numerical method is based on the potential flow theory and adopts a higher-order boundary element method with Green's function. First, motion RAOs were directly compared with the model test data by reference to validate the present numerical method. Then, numerical investigations were conducted to analyze the motion characteristics of the floating island by considering various modules shapes and arrangements. It was found that motion responses were reduced in a single central module compared to when divided central modules were used. Finally, the effect of modular arrangement on the motion responses in irregular waves was discussed. It was confirmed that multiple-layer outer modules are more effective in calming the central module than using single-layer outer modules, except under very long period conditions.

Keywords

Acknowledgement

This study was carried out with the support of the "Development of core source technology for marine green hydrogen for the realization of a carbon-neutral society" project of the Korea Research Institute of Ships & Ocean Engineering affiliated with the Korea Institute of Ocean Science and Technology and the "Development of prediction technology for local wave fields around offshore structures" project of the Research Institute of Marine Systems Engineering of Seoul National University. We would like to express our sincere appreciation for this financial support of our research.

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