Flow modeling and simulation of SCRIMP for composites manufacturing

As for the environmental protection, relatively inexpensive tooling and the ability to fabricate large parts with complex geometry, the vacuum bag molding (VBM) process and its variations such as SCRIMP might be the best choice to replace the traditional open molding processes. Since SCRIMP is often used to fabricate large sizes composites with a complex geometry, it is difficult to reach an acceptable design by the trial and error. Considerable expenses and time are compiled this way and obstruct the widespread use of VBM. Computer aided design and computer aided manufacturing (CAD/CAM), with its ability to simulate resin flowing through fiber mat, would be the best way to solve this problem. Many 2.25-dimensional (2.25D) flow models have been developed to simulate the mold filling processes in resin transfer molding (RTM). The resin infusion processes in VBM are similar to the mold filling process in RTM, but the following two issues must be considered: the resin flow from the channels or grooves to the fiber mats, and the compressibility of fiber mats. A hybrid 2.25D and 3D flow model to simulate the SCRIMP processes is proposed in the paper. According to the simulated results, sub-scale composite hulls (4') were fabricated. The simulated results agree well with the experimental results. (Example material: glass fiber reinforced polyester.)