Numerical simulation of the injection moulding process of short fiber composites by an integrated particle approach

In this study, we propose an integrated particle approach based on the coupling of smoothed particle hydrodynamics (SPH) and discrete element method (DEM) to predict the injection molding process of discrete short fibers. The fibers in the coupled SPH-DEM model are treated as non-rigid bodies to allow deformation and fracture. The interaction between resin and fibers is solved by a physical model to take into consideration of drag forces. Two cases of injection molding process with different volume fractions of short fibers are studied to predict the flow behaviors of fibers and resin. The numerical results qualitatively agree with previous experimental studies. It is found that the velocity contour of resin flow is parabolic in shape due to the velocity gradient near the wall boundaries and consequently the moving direction of fibers is in parallel with the flow direction of resin. Fiber accumulation is found in the case with higher content of short fibers.