Curvature effect on stress concentrations around circular hole in opened shallow cylindrical shell under external pressure

Circular holes are necessary either for access or for the passage of piping, ventilation ducts, uptakes, and electrical systems. A hole can be found in a missile skin, aircraft fuselage, ship hatch, boilers and submersible pressure hulls, amongst other numerous situations. Stress concentration around holes in shells is of relevant concern in the design stage. In particular, precisely analyzing the stress distributed around holes of the shell is critical for the shell's structural design. This work attempts to obtain stresses around a circular hole cut in an opened shallow cylindircal shell under external pressure. The finite element method is applied to examine how curvature and thickness influence stress concentrations around the circular hole. According to those results, the shell with a larger curved angle theta can resist the external pressure loading more effectively. In addition, if the curved angle a is tired, a gradual increase of the shell's thickness implies a gradual decrease of the stress. In addition, design data sheets regarding the stress distribution around the hole for different curved angles of the shell are developed, providing a valuable reference for the designer of a shell structure. (C) 1998 Elsevier Science Ltd. All rights reserved.