PMID- 18415043
OWN - NLM
STAT- PubMed-not-MEDLINE
DCOM- 20081003
LR  - 20211020
IS  - 1292-8941 (Print)
IS  - 1292-8941 (Linking)
VI  - 26
IP  - 1-2
DP  - 2008 May-Jun
TI  - Ultrasound velocimetry in a shear-thickening wormlike micellar solution: evidence 
      for the coexistence of radial and vorticity shear bands.
PG  - 3-12
LID - 10.1140/epje/i2007-10304-3 [doi]
AB  - We carried out pointwise local velocity measurements on 40 mM cetylpyridinium 
      chloride-sodium salicylate (CPyCl-NaSal) wormlike micellar solution using 
      high-frequency ultrasound velocimetry in a Couette shear cell. The studied 
      wormlike solution exhibits Newtonian, shear-thinning and shear-thickening 
      rheological behavior in a stress-controlled environment. Previous rheology, flow 
      visualization and small-angle light/neutron scattering experiments in the 
      shear-thickening regime of this system showed the presence of stress-driven 
      alternating transparent and turbid rings or vorticity bands along the axis of the 
      Couette geometry. Through local velocity measurements we observe a homogeneous 
      flow inside the 1mm gap of the Couette cell in the shear-thinning 
      (stress-plateau) region. Only when the solution is sheared beyond the critical 
      shear stress (shear-thickening regime) in a stress-controlled experiment, we 
      observe inhomogeneous flow characterized by radial or velocity gradient shear 
      bands with a highly sheared band near the rotor and a weakly sheared band near 
      the stator of the Couette geometry. Furthermore, fast measurements performed in 
      the shear-thickening regime to capture the temporal evolution of local velocities 
      indicate coexistence of both radial and vorticity shear bands. However the same 
      measurements carried out in shear rate controlled mode of the rheometer do not 
      show such rheological complexity.
FAU - Herle, V
AU  - Herle V
AD  - Institute of Food Science and Nutrition, ETH Zurich, Zurich, Switzerland. 
      vishwaherle@gmail.com
FAU - Manneville, S
AU  - Manneville S
FAU - Fischer, P
AU  - Fischer P
LA  - eng
PT  - Journal Article
DEP - 20080416
PL  - France
TA  - Eur Phys J E Soft Matter
JT  - The European physical journal. E, Soft matter
JID - 101126530
EDAT- 2008/04/17 09:00
MHDA- 2008/04/17 09:01
CRDT- 2008/04/17 09:00
PHST- 2007/09/17 00:00 [received]
PHST- 2008/02/22 00:00 [accepted]
PHST- 2008/04/17 09:00 [pubmed]
PHST- 2008/04/17 09:01 [medline]
PHST- 2008/04/17 09:00 [entrez]
AID - 10.1140/epje/i2007-10304-3 [doi]
PST - ppublish
SO  - Eur Phys J E Soft Matter. 2008 May-Jun;26(1-2):3-12. doi: 
      10.1140/epje/i2007-10304-3. Epub 2008 Apr 16.