A COMPRESSIBLE MODEL FOR THREE-DIMENSIONAL MELT FILLING AND GAS PENETRATION IN GAS-ASSISTED INJECTION MOLDING PROCESSES

摘要

The numerical prediction of three-dimensional melt filling and primary gas penetration in a clip-shaped square tube is conducted using compressible models in this paper. Similar to other fully three-dimensional methods, the full Navier-Stokes equations are solved together with the front transport equation using a front capturing approach. Different from previous studies assuming incompressible fluids in the filling process, the gas compressibility is considered in the proposed compressible model. For the case of a clip-shaped square tube, the gas penetration length and gas core size are compared among numerical predictions and experimental measurements, where a 3D Hele-Shaw model is also presented. The proposed compressible model has much better prediction accuracy than the 3D Hele-Shaw model. The proposed compressible model in the present study is proven to be accurate in the three-dimensional simulations of melt filling and primary gas penetration problems.