The European Physical Journal E

, Volume 31, Issue 3, pp 253–262

Droplets sliding on fibres

Regular Article

DOI: 10.1140/epje/i2010-10563-9

Cite this article as:
Gilet, T., Terwagne, D. & Vandewalle, N. Eur. Phys. J. E (2010) 31: 253. doi:10.1140/epje/i2010-10563-9

Abstract

We present the results of a combined experimental and theoretical investigation of oil droplets sliding on fibres. First, both the axisymmetric shape and the motion of a droplet on a vertical fibre are described. The motion is shown to result from a balance between the droplet weight and the viscous stresses. On a long-term range, the droplet loses some mass through coating the fibre, which decreases its velocity. In a second time, we rationalize the behaviour of a droplet that encounters a junction between vertical and horizontal fibres. Depending on its size, the droplet may cross the junction or remain blocked. The transition is well described by an ordinary differential equation equivalent to a damped harmonic oscillator truncated to the neighbourhood of the horizontal fibre. This simple system is the basic element for more complex fiber networks that would be useful in microfluidic applications involving droplets.

Copyright information

© EDP Sciences, SIF, Springer-Verlag Berlin Heidelberg 2010

Authors and Affiliations

  1. 1.Department of MathematicsMassachusetts Institute of TechnologyCambridgeUSA
  2. 2.GRASPUniversity of LiegeLiegeBelgium