Conceptual Design Principles for Non-Circular Pressurized Sandwich Fuselage Sections – a Design Study Based on a High-Order Sandwich Theory Formulation

Abstract

Results obtained as part of a design study regarding a non-circular pressurized sandwich fuselage section are presented. The originating problem is associated with preliminary studies for the “Global Range Transport” envisaged by the “New World Vistas” program of the United States Air Force. The modeling and analysis is conducted usinga high-order sandwich theory formulation in which the elastic response of each face laminate is accounted for, includingbending-stretching couplingand transverse shear deformations, and where the transverse flexibility of the core is included. The sandwich fuselage envisaged may contain flat, tapered and curved sandwich elements, and a high-order sandwich theory formulation is developed to analyze each of these configurations. The paper includes a presentation of the adopted high-order sandwich theory with special emphasis on the application for the analysis of sandwich panels with variable core thickness, and for the analysis of curved sandwich panels. Numerical results obtained for two different mid-plane asymmetric fuselage sections are presented and compared; one with constant core thickness, and one with varyingcore thickness.

Keywords

composite sandwich fuselage internal pressure loading high-order sandwich theory tapered sandwich panels curved sandwich panels mid-plane asymmetry design study

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