New confinement effects on the viscosity of suspensions

We present rheological experiments of confined suspensions at moderate concentrations. The analysis is carried out in the framework of a previous study on particle suspensions (DAVIT Y. and PEYLA P., EPL, 83 (2008) 64001) where simulations revealed the presence of unusual effects attributed to confinement, i.e. when the gap size (h) becomes closer to the particle size (d). Deviations from the usual viscosity trends were found. The present work investigates these features further and confirms the important role of the confinement. Extensions are made from the classical approach to the case of confined suspensions where the importance of the reduced gap h/d is taken into account. Copyright (C) EPLA, 2011