International Journal of Naval Architecture and Ocean Engineering

The Society of Naval Architects of Korea (대한조선학회)
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An optimization framework of a parametric Octabuoy semi-submersible design

  • Xie, Zhitian (Texas A&M University, Ocean Engineering Department, College Station) ;
  • Falzarano, Jeffrey (Texas A&M University, Ocean Engineering Department, College Station)
  • Received : 2019.05.27
  • Accepted : 2020.09.13
  • Published : 2020.12.31
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Abstract

An optimization framework using genetic algorithms has been developed towards an automated parametric optimization of the Octabuoy semi-submersible design. Compared with deep draft production units, the design of the shallow draught Octabuoy semi-submersible provides a floating system with improved motion characteristics, being less susceptible to vortex induced motions in loop currents. The relatively large water plane area results in a decreased natural heave period, which locates the floater in the wave period range with more wave energy. Considering this, the hull design of Octabuoy semi-submersible has been optimized to improve the floater's motion performance. The optimization has been conducted with optimized parameters of the pontoon's rectangular cross section area, the cone shaped section's height and diameter. Through numerical evaluations of both the 1st-order and 2nd-order hydrodynamics, the optimization through genetic algorithms has been proven to provide improved hydrodynamic performance, in terms of heave and pitch motions. This work presents a meaningful framework as a reference in the process of floating system's design.

Keywords

Acknowledgement

This research work was partially supported by the Ocean Systems Simulation & Control Laboratory, Texas A&M University. This support is gratefully acknowledged by the authors.

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