Three-dimensional numerical simulation of the filling process in rapid heating cycle molding

Rapid heating cycle molding (RHCM) is a novel injection molding technology. The mold cavity is heated up to a high temperature before the filling stage, usually higher than the glass transition temperature of the polymer. This new technology can be used to inject plastic parts with a shiny surface, no weld lines and no flow marks. A Rapid Heating Cycle Molding Simulation System (RHCM-S) was developed on the basis of an open software library OpenFOAM. The coupled velocity and pressure fields were solved using the PISO (Pressure Implicit with Splitting of Operations) algorithm. The VOF (volume of fluid) method was used to track the melt flow front. The filling process of polymer melt was simulated under various mold temperature. Mold temperature has significant influence on the flow field, temperature field, shear rate and injection pressure of the polymer melt. The results showed that the RHCM process with a relatively high mold temperature could improve the surface quality and performance of the plastic parts.