Long Glass Fiber Orientation In Thermoplastic Composites Using a Model That Accounts for the Flexibility of the Fibers

Mechanical properties of long glass fiber composites, used in various industrial applications, are dependant upon the fiber orientation within the part. To date, however, simulations with the ability to predict fiber orientation as a function of mold design are not available. In this study, a several options are explored to predict the orientation of long glass fibers in the concentrated regime which take the flexible nature of these fibers into account. Flow through a center gated disk geometry is simulated numerically for a high concentration of long glass fiber in a polypropylene (PP) matrix. For this, a 2D finite element (FEM) analysis was performed using the traditional Galerkin method for the balance equations and the discontinuous Galerkin method for the constitutive equations. Numerical results based on the Hele-Shaw approximation are compared with experiment to verify the models.