The flow and heat transfer of the melt in cavity have crucial effects on the final quality and properties of injection-molded parts.In order to predict the shrinkage

warpage and mechanical properties of the injection molded parts

it is necessary to predict the history of flow and heat transfer of melt accurately during the molding process.In this paper

the modeling of filling stage is based on the generalized Hele-Shaw flow of a compressible viscous fluid under non-isothermal conditions with consideration of the effects of compressibility and phase change.A hybrid FEM/FDM was employed to calculate the pressure field and temperature field

and the control volume method was adopted to advance the melt front.The compressible flow analysis of filling stage in plastics injection molding was implemented by using Visual C++.In order to keep each energy term be continuous across inter-element boundaries

each item of energy equation was discretized at the centroid of the elements

and then the energy equation at each vertex node was obtained by a weighted averaging scheme

thus the temperature field was estimated by solving the integrated energy equation of the whole calculation domain.Two parts were analyzed

and the comparison of numerical and experimental results verified the numerical algorithm and program of the compressible filling simulation.The numerical results also indicated that the compressibility of the material had important effects on the flow field of imbalance molds.