Effect of Distribution Media on Resin Impregnation Behavior during VaRTM Process

Multipoint measurements for resin flow during VaRTM process are carried out by using embedded fiber optic sensors to evaluate the effect of a resin distribution medium which is incorporated on a fiber preform as a surface layer on resin impregnation behavior. By simultaneously infusing epoxy resin into two glass fiber preforms with or without a distribution medium that are separated by a plastic film, resin amount impregnated through in-plane flow and out-of-plane flow via the distribution medium are compared. It has been indicated that resin amount impregnated through the out-of-plane flow via the distribution medium is found to be dominant especially for thinner fiber preform and be constant at each evaluated region of the resin flow. Numerical calculation for resin impregnation during the VaRTM process is also performed using coefficient of permeability both in in-plane and through-the-thickness direction in the fiber preform. The simulated resin amount impregnated through out-of-plane flow via the distribution medium is found to be constant during the impregnation process due to a constant slope angle of flow front, and be comparable with the experimental results.