Design of miniature floating platform for marginal fields

Abstract

This thesis presents the design of a novel type of miniature floating offshore platforms with a heave plate attached at the keel, suitable for developing deep-water marginal fields. This design features a small displacement, easy fabrication, reduced cost and a favourable motion performance in waves. The design process includes the preliminary estimation, hydrodynamic analysis and hull optimization. A self-developed model "Discrete Vortex Ring Model" (DVRM) to efficiently estimate the viscous drag due to the vortex shedding of the oscillatory heave plate is presented in details. This new model DVRM combined with the standard radiation/diffraction code WAMIT is used to analyse the effect of different geometric parameters on the motion behaviour of the platform. Finally, these two models are integrated into a genetic optimization algorithm to obtain a final optimal design.