Compaction And Fluid-Structure Interaction Leading to Fiber Displacement in Resin Infusion of Composite Manufacturing

Accurately predicting flow behavior in dry fiber preforms is essential for many liquid molding processes, including resin transfer molding (RTM). One of the main challenges in RTM is obtaining precise permeability values to ensure complete saturation of the preform during infusion.
Conventionally, permeability predictions are made using flow experiments on compacted dry fiber layers or by predictive flow simulation assuming an idealised preform. During RTM, the fabric undergoes initial compaction, subsequent relaxation at the arrival of the resin flow front, and eventually full saturation. To address the complex fluid-structure interactions, one approach would be to model the preform deformation during compaction and then study the change in fiber volume fraction during the steady state flow of resin. In this work, a mechanical model accounting for the frictional contact between the yarns was developed in order to predict the displacement during the initial compaction of the dry yarn assembly. The post-compaction deformed geometry is subsequently used within one-way coupled fluid-structure interaction simulations to predict the final fiber distribution within the modelled domain as well as the resultant steady state saturated permeability.