Optimisation of 3D printed composite fibre structures
File(s)
Author(s)
Luo, Yi-Rong
Type
Thesis
Abstract
A novel design approach for 3D printed fibre-reinforced composite structures that combines topology and fibre orientation optimisation is presented in this thesis. Solid Isotropic Material with Penalisation (SIMP) and Continuous Fibre Angle Optimisation (CAFO) method are developed to determine the optimal design of fibre-reinforced composites subject to a range of requirements including buckling resistance. A continuity equation is adopted to constrain fibre orientation and ensure continuous fibres within realistic fibre volume fractions. This results in fibre orientation with a corresponding and controllable variation of the fibre volume fraction. To ensure continuous fibre can be deposited, the manufacturability of the optimised results is ensured by introducing constraints controlled with two scalar fields to reconstruct fibre paths which are able to provide sufficient information to generate printer toolpaths. By considering realistic fibre volume fractions and manufacturability, numerical examples presented show that this approach successfully guarantees manufacturability with minimal loss of performance.
The design approach is developed to account for buckling resistance. The novelty of this extension lies in improving buckling resistance through varying both the topology layout and fibre orientation. Linear buckling analysis is applied to obtain the buckling characteristics. A stress field erosion and regularisation approach is adopted to alleviate the occurrence of spurious buckling modes during the optimisation process. Manufacturability is also considered while pursuing maximum buckling resistance. Numerical examples demonstrate a significant increase in buckling resistance and ensure manufacturability of optimal designs with little compromise in terms of stiffness.
The design approach is developed to account for buckling resistance. The novelty of this extension lies in improving buckling resistance through varying both the topology layout and fibre orientation. Linear buckling analysis is applied to obtain the buckling characteristics. A stress field erosion and regularisation approach is adopted to alleviate the occurrence of spurious buckling modes during the optimisation process. Manufacturability is also considered while pursuing maximum buckling resistance. Numerical examples demonstrate a significant increase in buckling resistance and ensure manufacturability of optimal designs with little compromise in terms of stiffness.
Version
Open Access
Date Issued
2024-09-03
Date Awarded
2024-12-01
Copyright Statement
Creative Commons Attribution NonCommercial Licence
License URL
Advisor
Hewson, Robert
Santer, Matthew
Publisher Department
Aeronautics
Publisher Institution
Imperial College London
Qualification Level
Doctoral
Qualification Name
Doctor of Philosophy (PhD)