Understanding lifecycle cost trade-offs for naval vessels: minimising production, maintenance, and resistance


Current optimisers struggle to explore the multi-disciplinary trade-space that defines vessel lifecycle cost. This paper tests an enhanced multi-objective collaborative optimiser on a three-objective hull and structural lifecycle costing problem. The optimiser extends multi-disciplinary collaborative optimisers by including goal-programming and a novel genetic algorithm at the discipline level. The optimiser finds the trade-space between vessel resistance, production cost, and structural maintenance cost. Simultaneous changes to the hullform geometry and structural scantlings are used to explore this design space. The approach is demonstrated on a naval optimisation problem. With fixed maintenance schedules, the trade-space is shown to be steeply walled. This topology indicates that single-discipline optimisation for lifecycle cost may lead to large increases in lifecycle cost for the disciplines not considered. In conclusion, multi-disciplinary optimisation is shown to be a useful tool for addressing lifecycle costing during design.

Ships and Offshore Structures