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abstract: 'We consider pressure-driven flows of electrolyte solutions in small channels or capillaries in which tracer particles are used to probe velocity profiles. Under the assumption that the double layer is thin compared to the channel dimensions, we show that the flow-induced streaming electric field can create an apparent slip velocity for the motion of the particles, even if the flow velocity still satisfies the no-slip boundary condition. In this case, tracking of particle would lead to the wrong conclusion that the no-slip boundary condition is violated. We evaluate the apparent slip length, compare with experiments, and discuss the implications of these results.'
author:
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    Eric Lauga\
    [*Division of Engineering and Applied Sciences, Harvard University*]{},\
    [*29 Oxford Street, Cambridge, MA 02138.*]{}
title: ' **Apparent slip due to the motion of suspended particles in flows of electrolyte solutions**'
---

Introduction
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The no-slip boundary condition of fluid mechanics states that the velocity of a viscous flow vanishes near a stationary solid surface [@batchelor]. Although it has been a crucial ingredient of our understanding of fluid mechanics for more than a century, it has been much debated in the past [@Goldstein], and, in the case of liquids, a complete physical 