Estudi computacional del comportament mecànic de biocompostos per a aplicacions en aeroestructures

Abstract

The present Bachelor Thesis aims to develop a computational framework to model composite materials made out of glass fibre and epoxy using the finite element analysis program MSC Nastran. A collaboration with the aeronautical company Singular Aircraft provides several glass fibre laminate layouts used in the structure of their UAV aircraft to be specifically characterized. Also, the associated manufacturing processes of these laminates employed by Singular Aircraft are experienced first-hand. The Classical Lamination Theory and MSC Nastran Transverse Shear Theory are used as linear elastic shell constitutive models for the simulation of a four-point bending test of the glass fibre/epoxy laminates. The development and utilization of a Python auxiliary code tool using composite material design guidelines from Bureau Veritas allows the obtention of analytical results on the bending test which align correctly with the MSCNastran numerical results. Awing beam for Singular Aircraft’s UAV aeroplane made out of carbon fibre and epoxy composite material is proposed as a replacement for the current aluminium beam. The Hoffman failure criterion is employed in MSCNastran to design an optimized laminate layout of the wing beam. The proposed solution achieves a surprisingly substantial weight reduction when compared to the aluminium beam and allows a wing-fuselage structural strut component to be removed from the plane which further improves the weight reduction of the plane. Finally, an analysis is made of the environmental impact of common composite materials in comparison with biocomposites and how they differ in mechanical performance.