Selecting the Best Heading for FPSOs in Santos Basin Considering the Wave Induced Motions Available to Purchase

The selection of the best heading considering the wave induced motion behavior is a design decision that should be taken in the early stages of the field development. Particularly for FPSOs with spread mooring pattern, that are not weathervane, this can bring the reduction of angular motions and accelerations, leading to better operational conditions, reduced wave induced loading acting on the FPSO deck structures and over the risers. The procedure adopted to select an optimized heading, is based in the analysis of several cases covering all the wave environment of Santos Basin, Offshore Brazil, and assessing parameters like roll motion and riser connection accelerations in order to select the optimum heading range. This problem has several input sea states, once the wave climate is defined by the extreme contour curves for the 100 year data. Another aspect is related to the combination of the FPSO loading conditions, which add more variables to the problem. A search algorithm have been implemented to enable the comparison of a large number of statistical results and to determine an adequate heading for the FPSOs.