Global/Local Analysis of Filling Behavior during Injection Molding for a Large Scale Plate with Micro Patterns

Abstract

Injection mold filling process was analyzed for a rectangular plate with micro patterns on the surface. For products with micro patterns whose dimensions are much larger than the dimensions of the micro patterns, numerical analysis may require a prohibitively large number of numerical grids. In order to solve this problem, anlaysis was done by separating the global flow through the base plate from the filling of the micro patterns. Global flow was analyzed using the generalized Hele-Shaw (GHS) model, while local flow for micro patterns was simulated by the Navier-Stokes equation. The boundary conditions, such as pressure and temperature, for the local analysis were obtained using the results of the global analysis. The proposed method was validated by experiments. Experimental observation showed good agreement with the numerical results. Effect of process parameters on the transcription fidelity was further examined. The numerical approach presented in this paper would enable a more efficient analysis and provide better understanding of filling behavior during injection molding of parts with micro patterns on the surface.

Rapid Numerical Estimation of Pressure Drop in Hot Runner System

“…Technologies and studies of numerical filling simulations for conventional injection molding process have matured [ 2 , 3 , 6 , 7 , 8 , 9 ]. In other processes, molding optimization is an important issue [ 10 ].…”