The linear stability of a two-layer flow of viscoelastic fluids on an inclined channel is examined. A simplified model is derived by using a weighted residual method combined with a long-wavelength expansion. A set of two coupled evolution equations for two fields, the film thickness and the flow rate , is obtained. Then, the correct threshold of instability of the interface is characterized analytically. The effect of the elasticity stratification on the stability of the interface is considered within the long-wavelength assumption.
Nous présentons une étude de stabilité linéaire de deux couches de fluides viscoélastiques s'écoulant par gravité dans un canal incliné. Un modèle simplifié basé sur une méthode aux résidus pondérés et une approximation polynomiale du champ des vitesses est développé. Il s'agit d'un système de deux équations couplées, décrivant l'évolution de l'interface et du débit local . Le modèle permet de prédire le seuil de l'instabilité de façon précise. L'effet de la différence d'élasticité sur la stabilité de l'interface est examiné dans le cadre de l'approximation des grandes longueurs d'onde.
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Mots-clés : Longues ondes, Instabilité, Fluides viscoélastiques, Méthode des résidus pondérés
Nadia Mehidi 1; Nawel Amatousse 1; Abdelmalek Bedhouche 1
@article{CRMECA_2015__343_5-6_354_0, author = {Nadia Mehidi and Nawel Amatousse and Abdelmalek Bedhouche}, title = {Interfacial instabilities of two-layer plane {Poiseuille} flows of viscoelastic fluids}, journal = {Comptes Rendus. M\'ecanique}, pages = {354--359}, publisher = {Elsevier}, volume = {343}, number = {5-6}, year = {2015}, doi = {10.1016/j.crme.2015.04.004}, language = {en}, }
TY - JOUR AU - Nadia Mehidi AU - Nawel Amatousse AU - Abdelmalek Bedhouche TI - Interfacial instabilities of two-layer plane Poiseuille flows of viscoelastic fluids JO - Comptes Rendus. Mécanique PY - 2015 SP - 354 EP - 359 VL - 343 IS - 5-6 PB - Elsevier DO - 10.1016/j.crme.2015.04.004 LA - en ID - CRMECA_2015__343_5-6_354_0 ER -
%0 Journal Article %A Nadia Mehidi %A Nawel Amatousse %A Abdelmalek Bedhouche %T Interfacial instabilities of two-layer plane Poiseuille flows of viscoelastic fluids %J Comptes Rendus. Mécanique %D 2015 %P 354-359 %V 343 %N 5-6 %I Elsevier %R 10.1016/j.crme.2015.04.004 %G en %F CRMECA_2015__343_5-6_354_0
Nadia Mehidi; Nawel Amatousse; Abdelmalek Bedhouche. Interfacial instabilities of two-layer plane Poiseuille flows of viscoelastic fluids. Comptes Rendus. Mécanique, Volume 343 (2015) no. 5-6, pp. 354-359. doi : 10.1016/j.crme.2015.04.004. https://comptes-rendus.academie-sciences.fr/mecanique/articles/10.1016/j.crme.2015.04.004/
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