Velocity oscillations in microfluidic flows of concentrated colloidal suspensions.
We study the pressure-driven flow of concentrated colloids confined in glass microchannels at the single-particle level using fast confocal microscopy. For channel to particle size ratios 2a/D[over ] less, similar30, the flow rate of the suspended particles shows fluctuations. These turn into regular oscillations for higher confinements (2a/D[over ] approximately 20). We present evidence to link these oscillations with the relative flow of solvent and particles (permeation) and the effect of confinement on shear thickening.
Isa
Lucio
L
SUPA, School of Physics & Astronomy, The University of Edinburgh, James Clerk Maxwell Building, The Kings Buildings, Mayfield Road, Edinburgh EH9 3JZ, United Kingdom.
Besseling
Rut
R
Morozov
Alexander N
AN
Poon
Wilson C K
WC