Stability analysis of a polymer film casting problem

Achraf Kallel 1 Elie Hachem 1 Francesca Rapetti 2 Yves Demay 2 Jean-François Agassant 1
1 CEMEF - Centre de Mise en Forme des Matériaux
2 JAD - Laboratoire Jean Alexandre Dieudonné
Abstract : The polymer cast film process consists of stretching a molten polymer film between a flat die and a drawing roll. Drawing instabilities are often encountered and represent a drastic limitation to the process. Newtonian fluid film stretching stability is investigated using two numerical strategies. The first one is a ‘tracking’ method, which consists of solving Stokes equations in the whole fluid area (extrusion die and stretching path) by finite elements. The interface is determined to satisfy a kinematic equation. A domain decomposition meshing technique is used in order to account for a flow singularity resulting from the change in the boundary conditions between the die flow region and the stretching path region. A linear stability method is then applied to this transient kinematic equation in order to investigate the stability of the stationary solution. The second method is a direct finite element simulation in an extended area including the fluid and the surrounding air. The time-dependent interface is captured by solving an appropriate level-set function. The agreement between the two methods is fair. The influence of the stretching parameters (Draw ratio and drawing length) is investigated. For a long stretching distance, a critical Draw ratio around 20 delimitating stable and unstable drawing conditions is obtained, and this agrees well with the standard membrane models, which have been developed 40 years ago. When decreasing the stretching distance, the membrane model is no longer valid. The 2D models presented here point out a significant increase of the critical Draw ratio, and this is consistent with experimental results.
Keywords : tracking strategy capturing strategy cast film draw resonance domain decomposition technique
Type de document :
Article dans une revue
Liste complète des métadonnées

Littérature citée [27 références]  Voir  Masquer  Télécharger
https://hal-mines-paristech.archives-ouvertes.fr/hal-01132639
Contributeur : Magalie Prudon <>
Soumis le : jeudi 18 août 2016 - 11:34:15
Dernière modification le : lundi 12 novembre 2018 - 11:05:13
Document(s) archivé(s) le : samedi 19 novembre 2016 - 19:57:18

Fichier

Kallel_JNMF2015.pdf
Fichiers produits par l'(les) auteur(s)

Identifiants

Collections

ENSMP | UNICE | INSTITUT-TELECOM | DIEUDONNE | PARISTECH | ENSMP_CEMEF | PSL | CFL | UNIV-COTEDAZUR

Citation

Achraf Kallel, Elie Hachem, Francesca Rapetti, Yves Demay, Jean-François Agassant. Stability analysis of a polymer film casting problem. International Journal for Numerical Methods in Fluids, Wiley, 2015, 78 (7), pp.436-454. ⟨10.1002/fld.4024⟩. ⟨hal-01132639⟩

Exporter

BibTeX TEI DC DCterms EndNote

Partager

Métriques

Consultations de la notice

484

Téléchargements de fichiers

406

Contact

support.ccsd.cnrs.fr
hal.support@ccsd.cnrs.fr
Logo CCSD