Mass Optimisation of Turbofan Engine Casing Made of Sandwich Structure
Materials of a high specific strength and stiffness are used in the aerospace industry to obtain the lowest possible aircraft mass. The object of analysis is the casing of the F124 turbofan engine. The axially compressed cylindrical part of this casing is considered. The aim of the paper is to analyse possible benefits of replacing the original ribbed metal casing with a sandwich structure. The sandwich structure (metal-fibre laminate) of titanium alloy faces and a flax fibre laminate core is proposed. Semi-analytical optimisation of a sandwich structure was performed including a polynomial approximation of the critical load with correction obtained based on numerical analysis. The best mass efficiency was obtained for a core to faces thickness ratio equal to about 4.
Keywordsthin-walled sandwich structure, flax laminate core, buckling, semi-analytical optimisation,
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