Abstract:
In industries such as aerospace, automobile, and petro-chemical, the composite overwrapped pressure vessels (COPV) have become a popular technique with the features of high stiffness-to-weight ratios and the advantages of leak-before-break. Based on the characteristics of filament winding process, a new technology of weldless connection of metal-lined COPV was proposed. The new technology used filament winding technology instead of welding forming process and designed a sealing groove on skirt length of the head to solve the problems of continuity and sealing between the head and the cylinder body. And an auxiliary forming tool was invented to apply filament winding process on this novel liner structure successfully. Then, the feasibility of the new structure was verified by hydraulic test. And the vessel could withstand the blasting design pressure about 110 MPa. Three damage modes were obtained by macroscopically inspecting of the vessel profile. Finally, based on a Chang-Chang failure criterion and the cohesive model, the finite element model of the novel structure was established by writing a user material subroutine VUMAT. The results show the delamination damage is the main damage mode and the fiber tensile fracture at the transition region of the head and cylinder is the main failure mode of the novel structure.