Numerical Study on Designing Truncated Mooring Lines for FPSO Stability Analysis Kim, Yun-Ho; Cho, Seok-Kyu; Sung, Hong-Gun; Seo, Jang-Hoon; Suh, Yong-Suk;
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 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.
Design of Truncated Mooring Line Model in KRISO's Deepwater Ocean Engineering Basin, Journal of Advanced Research in Ocean Engineering, 2015, 1, 4, 227
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