Mass Optimisation of Turbofan Engine Casing Made of Sandwich Structure

  • Elżbieta Szymczyk Military University of Technology
  • Jerzy Jachimowicz Military University of Technology
  • Krzysztof Puchała Military University of Technology
  • Wiesław Szymczyk Military University of Technology


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.


thin-walled sandwich structure, flax laminate core, buckling, semi-analytical optimisation,


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How to Cite
SZYMCZYK, Elżbieta et al. Mass Optimisation of Turbofan Engine Casing Made of Sandwich Structure. Computer Assisted Methods in Engineering and Science, [S.l.], v. 25, n. 2–3, p. 81-88, july 2019. ISSN 2299-3649. Available at: <>. Date accessed: 16 sep. 2021. doi: