Numerical Simulation of Gas-assisted Injection Molding Process for A Door Handle

A unified mathematical model is proposed to predict the short shot, primary and secondary gas penetration phenomenon in gas-assisted injection molding (GAIM) process, where the Cross-WLF model and two-domain modified Tait equation are employed to simulate the melt viscosity and density in the whole process, respectively. The governing equations of two-phase flows including gas, air and polymer melt are solved using finite volume method with SIMPLEC technology. At first, two kinds of U-shaped gas channels are modeled, where the shape corner and generous corner cases are studied. At last, as a case study, the short shot, primary and secondary gas penetration processes of a door handle are simulated. The numerical results show that the mathematical model can successfully depict the race-tracking and corner effects, which are very helpful for the design of GAIM.