Viscosity Monitoring of a Non-Newtonian Fluid for a Model Mold Using Energy Dissipation-based Flow Quantification

Abstract

Viscosity is a key factor in process control for the injection molding process, in which the mold shapes are often complex and fluids (polymer melts) are highly non-Newtonian that leads to diverse distributions of the shear rate and viscosity within the mold. In the present study, we propose a method to effectively measure viscosity corresponding to the shear rate that represents the average shear rate of the flow. An energy dissipation-based flow quantification was used to measure the effective viscosity and effective shear rate of a non-Newtonian fluid inside a modeled mold. The measurement was made through flow rate and pressure drop in both numerical and experimental methods. The viscosity measured using the proposed method was found to be consistent with rheological data which was within 32.6% errors.