Journal of Ocean Engineering and Technology (한국해양공학회지)

Korean Society of Ocean Engineers (한국해양공학회)
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Experimental Study on Reducing Motion of Circular Cylinder in Currents

조류 중 원형실린더 형상 구조물의 거동감소를 위한 실험적 연구

  • Lim, Jae Hwan (Ocean Science and Technology School, Korea Maritime and Ocean University) ;
  • Jo, Hyo Jae (Division of Naval Architecture and Ocean Systems Engineering, Korea Maritime and Ocean University) ;
  • Hwang, Jae Hyuk (Division of Naval Architecture and Ocean Systems Engineering, Korea Maritime and Ocean University) ;
  • Kim, Jae Heui (Division of Naval Architecture and Ocean Systems Engineering, Korea Maritime and Ocean University) ;
  • Lee, Tae Kyung (Division of Naval Architecture and Ocean Systems Engineering, Korea Maritime and Ocean University) ;
  • Choi, Yoon Woo (Division of Naval Architecture and Ocean Systems Engineering, Korea Maritime and Ocean University) ;
  • Lee, Min Jun (Division of Naval Architecture and Ocean Systems Engineering, Korea Maritime and Ocean University) ;
  • Kim, Young Kyu (Division of Naval Architecture and Ocean Systems Engineering, Korea Maritime and Ocean University)
  • 임재환 (한국해양대학교 해양과학기술전문대학원) ;
  • 조효제 (한국해양대학교 조선해양시스템공학전공) ;
  • 황재혁 (한국해양대학교 조선해양시스템공학전공) ;
  • 김재희 (한국해양대학교 조선해양시스템공학전공) ;
  • 이태경 (한국해양대학교 조선해양시스템공학전공) ;
  • 최윤우 (한국해양대학교 조선해양시스템공학전공) ;
  • 이민준 (한국해양대학교 조선해양시스템공학전공) ;
  • 김영규 (한국해양대학교 조선해양시스템공학전공)
  • Received : 2019.03.14
  • Accepted : 2019.08.12
  • Published : 2019.08.31
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Abstract

The development of marine technology is expected to increase the demand for marine plants because of increasing oil prices. Therefore, there is also expected to be an increase in the demand for cylindrical structures such as URF (umbilical, riser, flowline) structures and spars, which are used operating in various seas. However, a cylindrical structure experiences vortex induced motion (VIM) in a current. In particular, for risers and umbilicals, it is important to identify the characteristics of the VIM because interference between structures can occur. In addition, various studies have been conducted to reduce VIM because it is the cause of fatigue damage to structures. The helical strake, which was developed for VIM reduction, has an excellent VIM reduction performance, but is difficult to install on structures and has a negative effect on heave motion. Therefore, the purpose of this study was to supplement the shortcomings of the helical strake and develop a high-performance reduction device. In the reduction device developed in this study, a string is placed around the structure inside the flow, causing vibration. The vibration of this string causes a small turbulence in the flow field, reducing the VIM effect on the structure. Finally, in this study, the 2-DOF motion characteristics of models without a suppression device, models with a helical strake, and models with a string were investigated, and their reduction performances were compared through model tests.

Keywords

References

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