A Finite Element Model of a White-Metzner Viscoelastic Polymer Extrudate.
Abstract
A finite element model of a viscoelastic polymer melt characterized by a White-Metzner rheological equation of state was developed. For creeping flow wherein the inertia terms are negligible non-linear finite element equations were solved by a method of direct substitution termed Picard iteration. Four flow geometries were examined: cross channel, plane couette, entry, and step flow. A comparison of two bi-quadradic isoparametric element types (8 node 'serendipity' and 9 node 'Lagrange') showed general superior behavior of the Lagrange elements. The 'penalty' method of incompressible flow was used with the Galerkin method to formulate the finite element equation, yielding satisfactory behavior for creeping inelastic and viscoelastic flow. The non-linear equations yielded numerical convergence up to Weissenberg numbers of 0.01. Techniques of expanding this radius of convergence were examined and proposed for future effort. (Author)
Document Details
- Document Type
- Technical Report
- Publication Date
- Feb 01, 1981
- Accession Number
- ADA106740
Entities
People
- Brent R. Collins
Organizations
- Air Force Institute of Technology