The European Physical Journal E

, Volume 28, Issue 2, pp 159–164 | Cite as

Gravitational compression of colloidal gels

  • J. J. Liétor-Santos
  • C. Kim
  • P. J. Lu
  • A. Fernández-Nieves
  • D. A. Weitz
Regular Article

Abstract

We study the compression of depletion gels under the influence of a gravitational stress by monitoring the time evolution of the gel interface and the local volume fraction, \( \phi\), inside the gel. We find \( \phi\) is not constant throughout the gel. Instead, there is a volume fraction gradient that develops and grows along the gel height as the compression process proceeds. Our results are correctly described by a non-linear poroelastic model that explicitly incorporates the \( \phi\) -dependence of the gravitational, elastic and viscous stresses acting on the gel.

PACS

82.70.Gg Gels and sols 47.56.+r Flows through porous media 82.70.Dd Colloids 

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Copyright information

© EDP Sciences, SIF, Springer-Verlag Berlin Heidelberg 2008

Authors and Affiliations

  • J. J. Liétor-Santos
    • 1
  • C. Kim
    • 1
  • P. J. Lu
    • 1
  • A. Fernández-Nieves
    • 1
  • D. A. Weitz
    • 1
  1. 1.Department of Physics and HSEASHarvard UniversityCambridgeUSA

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