No-slip hydrodynamic boundary condition for hydrophilic particles

Abstract

We describe measurement and interpretation of the force acting on a smooth hydrophilic glass particle during rapid (1-100μms-1) approach to, and separation from, a hydrophilic glass plate in viscous concentrated aqueous sucrose solutions (0.001Pas<η<0.090Pas). We find that the force is accurately described by Reynolds lubrication theory with a no-slip boundary condition, even at maximum strain rates of up to 250000s-1. Compared to earlier studies of hydrodynamic forces on small particles, we reduce the uncertainty in the absolute particle-plate separation by using an evanescent-wave measurement of the separation. © 2007 The American Physical Society.