Numerical modelling of compaction induced defects in thick 2D textile composites

This paper introduces a novel approach to include the high transverse compliance of textile materials into conventional forming simulations, allowing for the compaction process of thick 2D textile composites to be simulated. With this approach, the textile is presented as a continuous material using mutually constrained shell and membrane elements, this allows for both the high tensile stiffness and low out-of-plane bending stiffness to be present within the model. To capture the through-thickness behaviour of the material, a compliant penalty contact is introduced which is able to capture the mechanical response of the material under compaction. By capturing the interaction between individual plies, the model is able to capture compaction induced wrinkle formation. The approach is used here to analyse the deformation behaviour of stacked layers compacted on to a male box tool to produce a C-section bracket. The model is validated against experimental results and used to assess the influence of key design and manufacturing parameters on defect formation.