Finite element analysis of multilayer coextrusion.

Hopkins, Matthew Morgan ; Schunk, Peter Randall ; Baer, Thomas A. (Proctor & ; Gamble Company, West Chester, OH) ; Mrozek, Randy A. (Army Research Laboratory, Adelphi, MD) ; Lenhart, Joseph Ludlow (Army Research Laboratory, Adelphi, MD) ; Rao, Rekha Ranjana ; Collins, Robert (Oak Ridge National Laboratory) ; Mondy, Lisa Ann

Sandia National Laboratories

关键词: Reflective Coatings;    Polymers;    Implementation;    36 Materials Science;    Thickness;   

DOI  :  10.2172/1029813
RP-ID  :  SAND2011-6136
RP-ID  :  AC04-94AL85000
RP-ID  :  1029813

美国|英语

来源: UNT Digital Library

【 摘 要 】

Multilayer coextrusion has become a popular commercial process for producing complex polymeric products from soda bottles to reflective coatings. A numerical model of a multilayer coextrusion process is developed based on a finite element discretization and two different free-surface methods, an arbitrary-Lagrangian-Eulerian (ALE) moving mesh implementation and an Eulerian level set method, to understand the moving boundary problem associated with the polymer-polymer interface. The goal of this work is to have a numerical capability suitable for optimizing and troubleshooting the coextrusion process, circumventing flow instabilities such as ribbing and barring, and reducing variability in layer thickness. Though these instabilities can be both viscous and elastic in nature, for this work a generalized Newtonian description of the fluid is used. Models of varying degrees of complexity are investigated including stability analysis and direct three-dimensional finite element free surface approaches. The results of this work show how critical modeling can be to reduce build test cycles, improve material choices, and guide mold design.