Safety Assessment Of Multi-body System In FPSO Side-by-side Offloading Operation

With the wide application of FPSO in ocean oil and gas engineering,offloading system plays an important role,especially the side-by-side offloading.In this paper,systematic evaluations of hydrodynamics and time-domain analysis of multi-body system in FPSO side-by-side offloading operation with a shuttle tanker which is connected by hawsers are performed.And optimize the system parameters.The main contents of this paper include:Analyses of hydrodynamic performance of multi-body,which consist of a FPSO and a tanker,are applied in two typical loading cases and three groups of distances between the two vessels.Taking into account for the hydrodynamic interactions,the first order wave force,RAO and second order wave force of each vessel are calculated.Comparative study is performed to analyze effects of the different parameters.Time-domain simulation analyses of multi-body system in offloading operation are performed.Different environmental conditions are calculated concerning the problems of relative motions of the two vessels and intensity of hawser.And safety environment can be achieved.Comparative study is performed to analyze effects of environmental conditions.In order to improve the safety properties of a side-by-side offloading system,various ways can be used,including enlarging the key factors properly,such as the size of the fenders and the hawsers as well as the number of hawsers,changing the length and position of hawsers,a better safety performance can be achieved.