An Optimization Method for the Concept Design of Semi-Submersible Offshore Accommodation Units

A methodology for the initial dimensioning and evaluation of semi-submersible offshore accommodation units by use of a novel optimization procedure is presented. The method developed has two main steps. First, the optimization procedure itself, in which a set of different configurations is considered and one by one optimized following a genetic algorithm in terms of cost estimates, whereas several other characteristics of the units are evaluated according to an embedded synthesis model. Second, the set of optimized geometries are run in commercial software for accurate seakeeping and stability analysis, where requirements’ compliance are checked. The final solution may then be chosen considering the trade-offs between cost and performance. In the last section of this paper, a case study is presented and the results obtained are discussed.