Numerical Modelling of Design Parameters for Manufacturing Polyester/Glass Composites by Resin Injection Pultrusion

Resin Injection Pultrusion (RIP) is an automated, continuous process and is one of the most cost-effective methods for manufacturing composite materials with constant cross sections (such as rod stock, beams, channels and tubing). In the present work, a 3-D finite volume technique was developed to advance the liquid resin flow front through the fibre reinforcement in the injection pultrusion process. The objective of this study was to improve fibre reinforcement wet-out and thus the quality of the pultruded part in an injection pultrusion process. The complete wet-out of the dry reinforcement by the liquid resin depends on various design and process parameters. The design parameters explored in this study were the aspect ratio of the final composite, injection slot width, injection slot location from inlet of injection chamber, and location of the multiple injection ports. The numerical model simulates the flow of polyester resin through glass rovings and predicts the impact of the design (geometric) parameters on wet-out, resin pressure field, and resin velocity field. The location of the liquid resin flow front has been predicted for an injection slot, as well as for five discrete injection ports.