Fracture analysis on the metal-lined hoop-wrapped cylinders with internal axial cracks

The metal-lined (steel-lined and aluminum-lined) hoop-wrapped cylinders wit h internal axial semi-elliptical cracks in the cylindrical portion center o f the metal-liner are modeled by a three-dimensional finite element method. Crack front regions are modeled using singular elements, whereas the rest of the cylinder is modeled using twenty-node hexahedron elements. Not only the cylindrical body, but also the neck and transition areas of the cylinde r, are considered in the modeling. The stress intensity factor KI and crack mouth opening displacement (CMOD) for the metal-lined hoop-wrapped cylinde rs are calculated. The influence of the hoop-wrapped materials, the interna l pressure and the crack sizes on the fracture behavior of these cylinders are discussed and the different fracture behaviors of the steel-lined hoop- wrapped cylinder and the aluminum-lined hoop-wrapped cylinder are discussed . (C) 1999 Elsevier Science Ltd. All rights reserved.