Hybrid twin models of fiber compaction for composite manufacturing based on dual kriging

During the preforming stage in Liquid Composite Molding (LCM), dry fibrous reinforcements are compacted to obtain a specific fiber volume fraction. Knowledge of the compaction force required to close the mold is an important information in Resin Transfer Molding (RTM), a composite manufacturing process in which the liquid polymer resin is injected through the fibrous reinforcement contained in a rigid and closed mold. In a related process called Vacuum Assisted Resin Infusion (VARI), the reinforcement is firstly compacted under vacuum, and then expands as the resin flows through the fiber bed. Numerous studies have been carried out to model the compression and relaxation of engineering textiles, which display a complex viscoelastic response under load, strongly dependent on fiber architecture. The various kinds of fibrous reinforcements and stacking sequences complicate the analysis. Experiments are necessary to provide reliable experimental data. Three families of reinforcements will be investigated under various experimental conditions: a Continuous Fiber Mat (CFM), a two-dimensional (2D) Non-Crimp Fabric (NCF) and a three-dimensional (3D) Interlock fabric. A new approach based on dual kriging, a multi-dimensional statistical interpolation method, is used to reproduce the compaction behaviors. A second approach, also based on dual kriging, is proposed to create Hybrid Twin (HT) models by combining experimental information on compaction with existing analytical models.