caa a22 4500 605466416 CHVBK 20210128100307.0 cr unu---uuuuu 210128e20150701xx s 000 0 eng 10.1007/s00397-015-0854-y doi (NATIONALLICENCE)springer-10.1007/s00397-015-0854-y Anomalous shear banding revisited with Rheo-NMR and Rheo-USV [Elektronische Daten] [Stefan Kuczera, Christophe Perge, Marc-Antoine Fardin, Timothy Brox, Martin Williams, Sébastien Manneville, Petrik Galvosas] A combined two-dimensional Rheo-NMR velocimetry and two-dimensional Rheo-USV approach is used to further elucidate the flow of a wormlike micellar solution in cylindrical Couette geometries. Recent experimental enhancements for both methods enable a more detailed description of the flow dynamics than available in the past. This enabled us to revisit and investigate shear banded flow utilizing improved spatial and temporal resolution, clearly confirming a departure from a simple lever rule for the micellar solution under study. Both experimental techniques observe different shear rates in the high shear rate band accompanied by a varying position of the interface between bands for different applied shear rates. Furthermore, spatially and temporally resolved velocimetry reveals various flow instabilities. Ultrasound measurements show vorticity undulations with wavelengths that scale linearly with the size of the high shear rate band. For high enough shear rates, the occurrence of turbulent bursts is detected in the USV case. However, no direct evidence of these bursts is found in the NMR measurements for equivalent shear rates, which we attribute so far to differences in the design of the shearing geometries. Springer-Verlag Berlin Heidelberg, 2015 Rheo-NMR nationallicence Rheo-USV nationallicence Wormlike micelles nationallicence Shear banding nationallicence Slip nationallicence Kuczera Stefan Victoria University of Wellington, SCPS, MacDiarmid Institute for Advanced Materials and Nanotechnology, Wellington, New Zealand aut Perge Christophe Laboratoire de Physique, École Normale Supérieure de Lyon, CNRS UMR 5672 -46 allée d'Italie, Université de Lyon, 69364, Lyon, cedex 07, France aut Fardin Marc-Antoine Laboratoire de Physique, École Normale Supérieure de Lyon, CNRS UMR 5672 -46 allée d'Italie, Université de Lyon, 69364, Lyon, cedex 07, France aut Brox Timothy Victoria University of Wellington, SCPS, MacDiarmid Institute for Advanced Materials and Nanotechnology, Wellington, New Zealand aut Williams Martin Institute of Fundamental Sciences, Massey University, Palmerston North, New Zealand aut Manneville Sébastien Laboratoire de Physique, École Normale Supérieure de Lyon, CNRS UMR 5672 -46 allée d'Italie, Université de Lyon, 69364, Lyon, cedex 07, France aut Galvosas Petrik Victoria University of Wellington, SCPS, MacDiarmid Institute for Advanced Materials and Nanotechnology, Wellington, New Zealand aut Rheologica Acta Springer Berlin Heidelberg 54/7(2015-07-01), 619-636 0035-4511 54:7<619 2015 54 397 https://doi.org/10.1007/s00397-015-0854-y text/html Onlinezugriff via DOI BK010053 XK010053 XK010000 Metadata rights reserved Springer special CC-BY-NC licence nationallicence 1 research-article jats NATIONALLICENCE NATIONALLICENCE NL-springer NATIONALLICENCE 856 40 https://doi.org/10.1007/s00397-015-0854-y text/html Onlinezugriff via DOI NATIONALLICENCE 700 1- Kuczera Stefan Victoria University of Wellington, SCPS, MacDiarmid Institute for Advanced Materials and Nanotechnology, Wellington, New Zealand aut NATIONALLICENCE 700 1- Perge Christophe Laboratoire de Physique, École Normale Supérieure de Lyon, CNRS UMR 5672 -46 allée d'Italie, Université de Lyon, 69364, Lyon, cedex 07, France aut NATIONALLICENCE 700 1- Fardin Marc-Antoine Laboratoire de Physique, École Normale Supérieure de Lyon, CNRS UMR 5672 -46 allée d'Italie, Université de Lyon, 69364, Lyon, cedex 07, France aut NATIONALLICENCE 700 1- Brox Timothy Victoria University of Wellington, SCPS, MacDiarmid Institute for Advanced Materials and Nanotechnology, Wellington, New Zealand aut NATIONALLICENCE 700 1- Williams Martin Institute of Fundamental Sciences, Massey University, Palmerston North, New Zealand aut NATIONALLICENCE 700 1- Manneville Sébastien Laboratoire de Physique, École Normale Supérieure de Lyon, CNRS UMR 5672 -46 allée d'Italie, Université de Lyon, 69364, Lyon, cedex 07, France aut NATIONALLICENCE 700 1- Galvosas Petrik Victoria University of Wellington, SCPS, MacDiarmid Institute for Advanced Materials and Nanotechnology, Wellington, New Zealand aut NATIONALLICENCE 773 0- Rheologica Acta Springer Berlin Heidelberg 54/7(2015-07-01), 619-636 0035-4511 54:7<619 2015 54 397