Modeling of the Resin Infusion Process using Multiphase Lattice Boltzmann for Predicting Voids in Textile Composites

This paper presents a methodology for multiphase fluid flow-based resin infusion process modeling for 3D woven textile composites. The fiber preform is treated as a porous media initially filled with air, liquid resin is injected and displaces the air out, however some air bubbles can be left behind. This displacement process is capillary dominated; therefore, our fluid flow characterization goes beyond the calculation of the permeability tensor to characterize the directional flow dependency of this material parameter, and includes the capillary pressure driven resin flow, by analyzing the interaction between the resin and air flowing within the porous media. As a part of the composite manufacturing process, these dry spots or voids can occur on the final composite part and introduce imperfections that can act as seeding points for possible mechanical failures, such as cracks or fractures. Hence, it is critical that the fiber reinforcements are wetted by the resin as much as possible to reduce the undesired effect of the voids. This multiphase flow problem in the complex composite micro-structure is solved by employing the Virtual Porous Media Lab (VPML®) software within SIMULIA® solution portfolio. The resin flow movement is predicted using this physics-based multiphase flow model and the formation and evolution of voids is captured and compared with experimentally observed void distributions in the same composite model.