Study of flow and RTD in a ZSK twin screw extruder

A prediction of blend morphology would require an understanding of the flow in various screw elements, distribution of shear and elongational flows as well as residence time distribution. The focus of this work is to develop new tools for prediction of molten flow and its effect upon blend morphology, As reported by Kiani and Franzheim(1,2), blend morphology can change in the fully filled as well as the partially filled sections of extruders. This work combines online residence time distribution measurement using Radio-Active Isotope technique with an advanced finite element technique to detail the flow distribution in different mixing geometries. The culmination of this joint effort should lead to a computational tool for optimization of different ZSK geometries for various processing tasks ( e.g., mixing, heat transfer, reaction).