An experimental study on riser hand-over operation between an installation vessel and an FPSO in regular waves

Abstract

Experimental and numerical studies were performed on the hand-over operation of a riser between an installation vessel and an FPSO. A series of model tests were conducted in the Ocean Engineering Basin of KRISO. In the model test, a riser truncation model was introduced considering the limited depth of the basin and pit diameter. In addition, a nonlinear time-domain numerical simulation was performed considering two-body interaction effects. The experimental data were directly compared with the simulation results in terms of vessel motion and wire tension under two load transfer conditions. The results show that two floating bodies during the riser hand-over operation experience significant hydrodynamic interaction. Under the low load transfer condition, the snapping phenomenon was clearly observed in the PIW tension. The discussion focuses on the effects of the two-body interaction, riser truncation, load transfer stages, and wave conditions.