Winding angle optimization of filament-wound cylindrical vessel under internal pressure

The maximum strength ratio and more uniform strength for all layers can be achieved by variation of winding angle of filament-wound (FW) vessel. The deformation and stresses of a thick-walled cylinder with multi-angle winding filament under uniform internal pressure are proposed. The stresses of each orthotropic unit of fiber layers, as well as longitudinal stress along the fiber direction, transverse stresses perpendicular to the fiber direction and shear stress in the fiber layer are derived analytically. An optimization model of FW closed ends vessel under uniform internal pressure subjected to Tsai-Wu failure criterion to maximize the lowest strength ratio through thickness with optimal variation of winding angle is built. Two optimization methods are adopted to find the optimized winding angle sequence through different ways, and their combination led to more efficient algorithm is suggested. The research shows that the material utilization and working pressure can be increased by proper winding angle variation, and several optimization winding angle sequence schemes are found for different thickness ratios cylindrical vessels with two typical composite materials E-glass/epoxy and T300/934, which are useful for many applications of FW vessel design and manufacture.