Abstract
Due to their exceptional benefits in terms of low cost, light weight, corrosion resistance, and fatigue resistance, composite overwrapped pressure cylinders with plastic liners (type IV) for high pressure hydrogen storage have attracted interest on a global scale. The sealing structure in the bottle mouth of the hydrogen cylinder is a type of material-dissimilar seal between metal and plastic, and it significantly affects the safety performance and fatigue life of Type IV cylinders. In this study, the failure behavior and mechanism of the sealing structure were investigated. The sealing performance of the bottle mouth structure was experimentally assessed by testing a type IV hydrogen cylinder with a working pressure of 70 MPa. In addition, ABAQUS was utilized to create a finite element (FE) model of the bottle mouth sealing structure, taking into account the cylinder’s deformation compatibility. On the basis of the FE model, the influence of rubber O-ring hardness, rubber O-ring thermal deformation, and the thermal sensitivity of the plastic liner’s mechanical characteristics on the structure of the bottle mouth seal was examined. These findings can contribute to the design and optimization of the sealing structure for a composite overwrapped pressure cylinder with a plastic liner for hydrogen storage.
