Abstract
Composite overwrapped pressure vessels (COPVs) represent a paradigm shift in lightweight pressure containment, achieving substantial mass savings over traditional metallic vessels. However, their widespread deployment remains constrained by challenges in design, fabrication, and qualification, most notably the risk of catastrophic stress rupture failure arising from stress concentrations under burst and dynamic loading conditions. To address these concerns, this study undertakes a rigorous optimization of COPV design parameters, with particular emphasis on the influence of winding angles and lay-up patterns on burst pressure performance. Advanced finite element analysis using ABAQUS was employed to develop sixteen Aluminum/Flax–Sisal hybrid composite COPV models incorporating a 4 mm aluminum liner and varied ply configurations. In contrast to conventional synthetic fiber overwraps, the proposed natural synthetic hybrid system offers a sustainable alternative with competitive load-carrying capability. Comparative stress analyses indicate that optimized hybrid lay-ups can achieve burst pressures comparable to synthetic composites while reducing weight and environmental impact, thereby establishing their viability for safe and efficient pressure containment. A systematic investigation of fiber orientations and stacking sequences, conducted under isoperimetric thickness constraints, identified an optimal [24.5°, 24.5°] ply sequence in a PP winding pattern, achieving a maximum burst pressure of 10.295 MPa with ten reinforcement layers. Stress strain evaluations revealed a predominantly uniform membrane stress distribution, with critical stress concentrations localized at the polar boss interface. These findings provide valuable insights for enhancing the performance, durability, and operational safety of COPVs in high-demand storage, aerospace, and industrial applications.