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Numerical Study on Designing Truncated Mooring Lines for FPSO Stability Analysis

FPSO 안정성 평가를 위한 절단계류선 모델링 수치 연구

  • 김윤호 (한국해양과학기술원 선박해양플랜트연구소) ;
  • 조석규 (한국해양과학기술원 선박해양플랜트연구소) ;
  • 성홍근 (한국해양과학기술원 선박해양플랜트연구소) ;
  • 서장훈 (삼성중공업(주)) ;
  • 서용석 (삼성중공업(주))
  • Received : 2014.07.01
  • Accepted : 2014.10.24
  • Published : 2014.10.31

Abstract

In this paper, a numerical analysis for an internal turret moored vessel located at a 400-m water depth is conducted. The target vessel has an internal turret that is located at the 0.2 Lpp position from the fore-side, with $3{\times}4$ complex mooring lines installed around the turret circumference. To investigate the motion response of the vessel and the structural reliability of the lines, model tests were conducted. The KRISO ocean basin has a water depth of 3.2 m, which represents 192m using a scaling of 1:60. In order to precisely represent the real-scale condition, equivalent mooring lines needed to be designed. Truncated mooring lines were designed to supplement the restriction of the flume's water depth and increase the reliability of the model testing. These truncated mooring lines were composed of two different chains in order to match the pre-tension, simultaneously restoring the curve and variation in the effective line tension. The static similarities were compared using a static pull-out test and free decaying test, and the dynamic similarities were matched via a regular wave test and combined environments test. Consequently, the designed truncated mooring system could represent the prototype mooring system relatively well in the aspects of kinematics and dynamics.

Keywords

References

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Cited by

  1. Study on Design of Truncated Mooring Line with Static Similarity in Model Test Basins vol.31, pp.4, 2017, https://doi.org/10.26748/KSOE.2017.08.31.4.257