Origin of the negative wake behind a bubble rising in non-Newtonian fluids - Archive ouverte HAL Accéder directement au contenu
Article Dans Une Revue Chemical Engineering Science Année : 2006

Origin of the negative wake behind a bubble rising in non-Newtonian fluids

Résumé

The present work aims at understanding the behavior of individual bubbles in non-Newtonian fluids. By means of a Particle Image Velocimetry (PIV) device, the complete flow field around either a single non-spherical bubble rising in polyacrylamide (PAAm) solutions or a solid sphere settling down in the same fluids shows for the first time the similar coexistence of three distinct zones: a central downward flow behind the bubble or the sphere (negative wake), a conical upward flow surrounding the negative wake zone, and an upward flow zone in front of the bubble or the sphere. This excludes then the possible influence of the interface deformation on the negative wake. A theoretical lattice Boltzmann scheme coupled to a sixth-order Maxwell model was developed for computing the complex flow field around a solid sphere. The good agreement with the experimental measurements provides evidence that the physical mechanism responsible for the negative wake in such fluids could be related to the fluid's viscoelastic properties.
Fichier non déposé

Dates et versions

hal-00282320 , version 1 (27-05-2008)

Identifiants

  • HAL Id : hal-00282320 , version 1

Citer

M. Kemiha, X. Frank, S. Poncin, H.-Z. Li. Origin of the negative wake behind a bubble rising in non-Newtonian fluids. Chemical Engineering Science, 2006, 61 (12), pp.4041-4047. ⟨hal-00282320⟩

Collections

CNRS UNIV-LORRAINE
34 Consultations
0 Téléchargements

Partager

Gmail Facebook X LinkedIn More