Non-Circular Cylindrical Shells of Mid-Plane Asymmetric Construction Subjected to an Internal Pressure

Abstract

In future large cargo transport aircraft, such as the Global Range Transport proposed in the New World Vistas program of the United States Air Force, it is likely that the fuselage cross-section will be non-circular. For efficient cargo space, the fuselage cross-section being investigated is that of a rectangle with rounded corners. In order to minimize the resulting bending stresses, sandwich construction is being investigated, and in particular a mid-plane asymmetric construction is being studied to utilize bending-stretching coupling to minimize these bending stresses still further in the sandwich construction. The bending-stretching coupling can be introduced by using sandwich faces of different thickness and/or different materials and/or different fiber orientation of the composite material. The Theorem of Minimum Potential Energy is employed to investigate the subject problem. In this study, the lateral deflection that is assumed, a separable solution, employs the results of previous investigations: for the axial function, the lateral deflection of the analytical solution for a circular cylindrical shell with various boundary conditions subjected to an internal pressure is used; for the circumferential component of the lateral displacement, the series solution used previously by the authors for a ring solution of the same circumferential shape and loading is used. The magnitude and location of the maximum stresses in each face for each material system is then determined, and the maximum deflection is also found. Thus, the mechanics of the elastic behavior of this elastic thin walled shell subjected to this loading is adequately described. Some example problems are discussed, and various material systems and geometries are compared.