| Titre : |
Numerical simulation of the film casting process |
| Type de document : |
texte imprimé |
| Auteurs : |
Evan Mitsoulis, Auteur ; M. Beaulne, Auteur |
| Année de publication : |
1999 |
| Article en page(s) : |
p. 261-275 |
| Note générale : |
Bibliogr. |
| Langues : |
Anglais (eng) |
| Index. décimale : |
668.9 Polymères |
| Résumé : |
Numerical simulations have been undertaken for the film-casting process with viscoelastic fluids. Viscoelasticity is described by an integral constitutive equation of the K-BKZ type with a spectrum of relaxation times, which fits well experimental data for shear and extensional viscosities and the normal stresses measured in shear flow. Non-isothermal conditions are considered by applying the Morland-Lee hypothesis, which incorporates the appropriate shift factor and pseudo-time into the constitutive equation. A one-dimensional model derived from the conservation of momentum is used to approximate the thickness, while the stress free-surface condition is used to approximate the width. The resulting system of differential equations is solved using the finite element method and the Newton-Raphson iterative scheme. The method of solution was first checked against the Newtonian and Maxwell results for different film geometries. The simulations are compared to available experimental data and previous simulations in terms of film thickness, film width, and film temperature. Agreement between the experiments and the current simulations is considered good with subtle differences. Agreement is also considered good between the current one-dimensional simulations and previous two-dimensional simulations for viscoelastic fluids, in terms of width and thickness. The one-dimensional model is advantageous since the algorithm is relatively simple, convergence is almost guaranteed, and the computing time is short. |
| Note de contenu : |
- MATHEMATICAL MODELING
- CONSTITUTIVE EQUATIONS : Isothermal newtonian model - Isothermal upper-convected Maxwell (UCM) differential model - Study of silagy et al - Isothermal upper-convected maxwem (UCM) differential model - Current study - Non-isothermal modified K-BKZ integral constitutive model -
- METHOD OF SOLUTION
- RESULTS AND DISCUSSION : Film casting of a newtonian fluid - Film casting of an upper-convected Maxwell (UCM) fluid - Comparison with three-dimensional simulations - Comparison with two-dimensional simulations - Non-isothermal film casting of polymer melts - Non-isothermal film casting of polymer melts - a parametric study |
| DOI : |
10.3139/217.1554 |
| En ligne : |
https://drive.google.com/file/d/1LZUwzCGYNHSBxzRIGvfM23OmH-qROS5N/view?usp=drive [...] |
| Format de la ressource électronique : |
Pdf |
| Permalink : |
https://e-campus.itech.fr/pmb/opac_css/index.php?lvl=notice_display&id=16137 |
in INTERNATIONAL POLYMER PROCESSING > Vol. XIV, N° 3 (09/1999) . - p. 261-275
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Numerical simulation of the film casting process in INTERNATIONAL POLYMER PROCESSING, Vol. XIV, N° 3 (09/1999)
