Vortex-Induced Motion of a Novel Mono-Column FPSO in Waves and Currents

Abstract The mono-column FPSO platform has recently attracted more attention from researchers due to its advantage of stability in waves and currents relative to the traditional Spar platform with the larger draft. However, the heave motion of the mono-column platform becomes a concomitant disadvantage for this type of platform. The submersible appendix is usually designed to suppress the heave motion of the platform, which could interrupt the flow patterns around the column. The vortex-induced motion (VIM) of the platform could be much different from the original column or Spar platform. The present article initially investigates the VIM performances of a novel mono-column FPSO with a heave suppression structure. The performance is studied numerically in the case of both currents only and currents with waves, respectively. The dependency of mesh and time step are observed to validate the numerical model. The characteristics of inflow and cross-flow responses are analyzed comprehensively. Further, the influence of waves is found limited to the overall responses of vortex-induced motion in the given cases. The present article is significant to the design of the novel mono-column FPSO platform and provides references for further study of vortex-induced motion.