Design optimization of composite cylindrical shell under hydrostatic pressure

The paper presented an optimization design of filament-wound composites pressure hull subjected to hydrostatic pressure for underwater vehicle application. An Optimization Platform was set up by interworking a genetic algorithm and numerical simulation. A sensitivity analysis was performed to study the effects of design variables on the buckling pressure, material failure pressure and design pressure. Results revealed that the buckling pressure or the material failure pressure would restrict the design pressure of different thickness of pressure shell. Application of composite materials for deep-water pressure shell had more reserve buoyancy, which would result in miniaturizing the size of underwater vehicles. Effects of different type of ring-stiffened configuration were analyzed. Mid-stiffened configuration can enhance stability significantly. End-stiffened configuration can minimize the effect of stiffness mismatch. Results of this study provided a valuable reference for designers of underwater vehicles. The paper suggest that new way of enhancement, such as variable thickness, composites ribs would be used to solve the conflict of buckling pressure and material failure pressure.