Structural design and damage failure analysis of cone-cylinder integrated composite case

The cone-cylinder integrated composite case is an emerging bearing structure form of the solid rocket motor, the fiber wound structure is complex compared with the straight cylindrical structure, and the failure process and the ultimate failure mode when undertaking the internal pressure load are not clear. Therefore, a cone-cylinder integrated composite case simulation model was built to study the trajectory patterns, failure mode, fracture position, and burst pressure. A significant stress mutation exists at the transition region of the straight and the cone parts, which weakens the undertaking capacity of the composite case. All fiber fracture at this region of hoop layer exhibits fracture ultimately. The study results can apply a reference when designing and failure analysis for the cone-cylinder integrated composite case.