Ocean Systems Engineering

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Experimental and numerical study on motion responses of modular floating structures with connectors in waves

  • Dong-Hee Choi (Department of Naval Architecture and Ocean Engineering, Seoul National University) ;
  • Jae-Min Jeon (Department of Naval Architecture and Ocean Engineering, Seoul National University) ;
  • Min-Ju Maeng (Department of Naval Architecture and Ocean Engineering, Seoul National University) ;
  • Jeong-Hyeon Kim (Department of Naval Architecture and Ocean Engineering, Seoul National University) ;
  • Bo Woo Nam (Department of Naval Architecture and Ocean Engineering, Seoul National University)
  • Received : 2024.06.15
  • Accepted : 2024.09.13
  • Published : 2024.09.25
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Abstract

In this study, the wave-induced motion responses of modular floating structures (MFS) was investigated through a series of experiments in a two-dimensional wave tank. A 1:63 scale model test was conducted using a 1-by-2 modular floating structure consisting of two modules and connectors. Two different types of connectors were considered: a pitch-free hinge and rigid connector. The numerical analysis was performed based on the higher-order boundary element method (HOBEM) and wave Green function with potential flow theory. First, the heave and pitch RAOs of the modules from the regular wave tests were directly compared with numerical analysis results. Next, the motion spectra and their statistical values from the irregular wave tests were compared with the numerical analysis results. The study revealed that the sheltering effect of the weather side module led to a reduction in motion of the lee side module. The numerical analysis showed good agreement with the experimental data, demonstrating the validity of the numerical method. Additionally, the rigid connector, which strongly constrain all six degrees of freedom, significantly reduce pitch motion, making the modules behave as a single rigid body.

Keywords

Acknowledgement

This research was supported by the Korea Agency for Infrastructure Technology Advancement (KAIA) grant funded by the Ministry of Land, Infrastructure and Transport (Grant RS-2023-00250727) through the Korea Floating Infrastructure Research Center at Seoul National University.

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