Effect of Wave Steepness on Yaw Motions of a Weathervaning Floating Platform

Experimental studies were carried out at the Institute for Ocean Technology, Canada, in collaboration with UWA to assess the response of a 1:60 scaled Floating Production Storage and Offloading (FPSO) model in complex sea states. The model was moored by means of four instrumented mooring lines attached to an internal turret. As part of these experiments a series of model tests in regular waves were conducted. Numerical computations for linear motion response of the FPSO were conducted using well established boundary element packages. It is found that the model deviated significantly from linear behaviour in cases where there were involuntary heading changes. These changes were further understood by looking at the phasing between surge and sway accelerations