Numerical and experimental analysis on resin injection pultrusion (RIP) process - using macroscopic and microscopic approaches

Resin Injection Pultrusion (RIP) is a new composite manufacturing process, which combines the advantages of the conventional pultrusion process and the Resin Transfer Molding (RTM) process. In this study, a computer simulation tool, based on the Control Volume Finite Element Method (CV/FEM) and other numerical techniques, has been developed for resin flow, heat transfer, and resin curing in RIP. This simulation technique is then used to predict the processing conditions and to provide useful information for the process design. Fiber package design is analyzed based on the permeability and compressibility modeling, and the computed resin impregnation pattern and pressure distribution inside the fiber stack. Conversion profiles in the heating section of the pultrusion die can also be obtained using the simulation tool. It is found that poor fiber wetting during resin impregnation and low resin conversion at die exit are the two major reasons for blister formation. The computer model developed in this study is also capable of simulating the transient heat transfer in both the die block and the composite, which can provide useful information for both the puling force prediction and the blister formation analysis. Experiments on both the conventional pultrusion and the RIP have been carried out, and the experimental data are used to verify the simulation results.; Polymeric fluid flows in micro-channels are of interest in polymer processing applications. They were studied numerically using the Finite Element Method (FEM) and Molecular Simulation technique, i.e. the CONNFFESSIT approach. A computer code was developed for both one-dimensional and two-dimensional viscoelastic flows based on this approach. Both slip boundary conditions and periodic boundary conditions were considered. Applications of this simulation code could be polymeric fluid flows through porous media and micro-channel flows in micro-fluidics. The code is first applied to the simple shear flow case where analytical solutions are available for comparison. Other flow cases, such as periodic flow of polymeric fluids though an idealized fiber bed and flow over a gas bubble with a presumed shape in a tube, were also studied to show the potential of the simulation code in handling complex flows.