Flow simulation of coextrusion feed-blocks

Abstract

The paper discusses how flow simulation is used to analyze and optimize the design of the coextrusion feed-blocks. The results help to explain the reason behind certain design arrangements. A case study of a problem encountered in an actual, three-layer film production will be used to demonstrate how the design of the feed block merge section and the material flow properties, especially the elongational viscosity, can create conditions for the "wave" type interfacial instability.