Component Approach for Confident Predictions of Deepwater CALM Buoy Coupled Motions: Part 1 — Philosophy

This paper describes a component approach of coupled motions for design of deepwater CALM offloading system in West Africa environment. Confident offloading buoy motions coupled with mooring and offloading line dynamics is identified as one of the key design challenges. In deepwater systems, components from the wave forces (exciting forces and radiated wave forces), viscous damping forces and mooring forces follow different scaling laws. We can not properly scale up the measured global responses of the coupled system to full-scale to verify the design. Component approaches overcome many of the test engineering and scale up weaknesses associated with truncated physical modeling. An effective application of a component approach develops a model test strategy for the purpose of validating the design analysis tools. In this paper we present a strategy for model testing, design tool validation and full-scale analyses. Differences between the component approach and the current industry practice are highlighted.