A FINITE-ELEMENT METHOD FOR FLOW IN COMPRESSION MOLDING OF THIN AND THICK PARTS

Based on Barone and Caulk's model and a generalized variational functi onal, a finite element simulation was developed for the compression mo lding of thin and thick parts. For solving the u-v-p type equations, a n element-based penalty method and a mixed formulation were implemente d. Numerical results show that the new model gives better accuracy in velocity and velocity gradient than the Hele-Shaw formulation for case s where both models are appropriate. Predictions of velocity and its g radient by the model are compared with other FEM results and BEM solut ions. Using a fixed base mesh that covers the mold cavity, a new techn ique was developed for tracking the moving flow front. Temporary eleme nts and nodes are generated for the filled part of elements intersecte d by the flow front. This method allows a smooth representation of the flow front and has exact boundary conditions on the flow front. The s cheme is demonstrated for compression molding of an elliptical and an L-shaped charge.