Level Set Method for Fully Thermal-Mechanical Coupled Simulations of Filling in Injection and Micro-Injection Molding Process

In this work we tackle a more theoretical aspect of micro-injection molding, to better understand physics during the process, through numerical simulations of cavity filling. We developed a two phase flow approach by the use of COMSOL Multiphysics®. In a first step, a Level Set model is applied to several configurations: Newtonian and non Newtonian fluid (Cross viscosity law), coupled with a thermal equation and a thermal dependence of the viscosity (Williams-Landel-Ferry law). We take into account the unsteady thermal behavior of the mould while injecting the polymer into the cavity. Finally, as air –trapping often occurs in the injection molding process, we present some results considering a pseudocompression law (low Mach number) for the air. To conclude, we show the ability of the COMSOL model to simulate polymer filling in microfeatures.