https://doi.org/10.1140/epje/i2012-12091-0
Colloquium
Instabilities in wormlike micelle systems
From shear-banding to elastic turbulence
1
Laboratoire Matière et Systèmes Complexes, CNRS UMR 7057-Université Paris Diderot, 10 rue Alice Domon et Léonie Duquet, 75205, Paris Cédex 13, France
2
Department of Mechanical Engineering, Massachusetts Institute of Technology, 77 Massachusetts Avenue, 02139-4307, Cambridge, MA, USA
3
The Academy of Bradylogists, Paris, France
* e-mail: sandra.lerouge@univ-paris-diderot.fr
Received:
6
April
2012
Revised:
1
August
2012
Accepted:
2
August
2012
Published online:
25
September
2012
Shear-banding is ubiquitous in complex fluids. It is related to the organization of the flow into macroscopic bands bearing different viscosities and local shear rates and stacked along the velocity gradient direction. This flow-induced transition towards a heterogeneous flow state has been reported in a variety of systems, including wormlike micellar solutions, telechelic polymers, emulsions, clay suspensions, colloidal gels, star polymers, granular materials, or foams. In the past twenty years, shear-banding flows have been probed by various techniques, such as rheometry, velocimetry and flow birefringence. In wormlike micelle solutions, many of the data collected exhibit unexplained spatio-temporal fluctuations. Different candidates have been identified, the main ones being wall slip, interfacial instability between bands or bulk instability of one of the bands. In this review, we present experimental evidence for a purely elastic instability of the high shear rate band as the main origin for fluctuating shear-banding flows.
Key words: Colloquium
© EDP Sciences, SIF, Springer-Verlag Berlin Heidelberg, 2012
