Speeding up of Sedimentation under Confinement

Condensed Matter journal club

Speeding up of Sedimentation under Confinement

  • Event time: 11:30am
  • Event date: 24th May 2013
  • Speaker: Juho Lintuvuori (Formerly School of Physics & Astronomy, University of Edinburgh)
  • Location: Room 2511,

Event details

Abstract

We show an increase of the sedimentation velocity as small particles are confined in circular capillaries. In general, confinement slows down sedimentation. But, we show that at low Reynolds numbers and in 1D confinement this is not the case. Particle sedimentation velocity is not homogeneous, which can lead to the formation of structures. These structures are enhanced and stabilized in the presence of walls and in the absence of other dissipative mechanisms. As a consequence, it is possible to achieve sedimentation velocities that even exceed the Stokes velocity. The segregation at critical capillary diameters has been directly observed using a large scale model. These simple experiments offer a new insight into the old problem of sedimentation under confinement.
PRL 110 article 178302 (2013)
pdf version

Authors

S. Heitkam, Y. Yoshitake, F. Toquet, D. Langevin, A. Salonen