文档介绍：Rheol Acta 35:494-507 (1996)
© Steinkopff Verlag 1996
Jacques Guillet Experimental and numerical study of entry flow
Pascale Revenu
Yves B6reaux of low-density polyethylene melts
Jean-Robert Clermont
Abstract The present work deals main of the total flow domain, the
Received: 24 July 1995
Accepted: 12 July 1996 with experimental and numerical "peripheral stream tube", close to
features of entry flows of two the wall of the converging duct per-
polyethylene melts, namely a linear mits to relate the results of the
low-density polyethylene (LLDPE) numerical simulation to experimen-
J. Guillet • P. Revenu
Laboratoire de Rh6ologie and a low-density polyethylene tal flow characteristics as total and
de Matibres Plastiques (LDPE) in an axisymmetric con- entrance pressure drops. The agree-
Universit6 Jean- verging geometry. The study also ment is good for the total pressure
Facult6 des Sciences et Techniques involves rheological characterization losses, but, concerning LDPE, a
23, Rue Paul Michelon of the polymers and determination lack of consistency remains for the
42023 Saint-Etienne Cedex 02, France
of flow parameters, at 160°C. For entrance pressure drop.
Y. B6reaux • Dr J.-R. Clermont (~) both fluids, the data are fed into a
Laboratoire de Rhdologie viscoelastic integral Wagner con- Key words Polyethylene melts -
UMR 5520 (CNRS), INPG Grenoble stitutive equation. The numerical entry flows - pressure drops -
and Universit6 Joseph-Fourier
Domaine Universitaire flow simulations are performed by stream-tube methods -
BP No. 53 using a stream-tube mapping Wagner integral model
38041 Grenoble Cedex 9, France analysis. Consideration of a sub-do-
and the prediction of flow phenomena occurring in pro-
Introduction cessing rheology.
The numerous papers in the literature attest to the in-
A main objective in rheology concerns the use of con- terest and progress of research in this field, in relation to
stitutiv