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Master 2: International Centre for Fundamental Physics
INTERNSHIP PROPOSAL
(One page maximum)
Laboratory name: Laboratoire de Physique des Solides
CNRS identification code: 8502
Internship director’s name: Salonen Anniina
E-mail: [email protected]
Phone number: 01 69 15 53 88
Web page: https://www.equipes.lps.u-psud.fr/sil/
Internship location: Laboratoire de Physique des Solides, bâtiment 510, Université Paris
Sud, 91405 Orsay
Thesis possibility after internship: NO
Instability or a flux argument – which controls sedimentation in capillaries?
Particles that are heavier than the solvent in which they are suspended in sediment, they flow
down to the bottom of the recipient. This can be a nuisance, but it is a useful way to separate
material in industrial processes, and it also responsible in Nature for the river delta formations
for example. Due to the large number of particles interacting via a fluid, the sedimentation
process is complicated. We have previously studied the sedimentation of solid particles in small
glass capillaries 1, where the proximity of walls (confinement) can influence the process.
We have since started working on the problem of sedimentation starting from a homogenous
block, as seen in the Figure below. In this case, depending on how compact the sediment is it can
melt like a solid or destabilize like a fluid. In the case of a fluid destabilization, as seen in the
Figure below the process resembles closely at a Rayleigh-Taylor instability. Once the flow has
stabilized and reached a steady state the transport of particles can be followed. The results of the
preliminary experiments suggest two possibilities for fixing the rate of particle transport: 1) It is
set by the initial instability or 2) The sedimentation proceeds as fast as possible. The aim of the
internship is to show which of these possibilities is correct (or that it is neither and a 3rd option
that we have not imagined). There are also
possibilities to study the process in inclined
capillaries, where the process resembles more
that of granular flow on inclined planes.
We are looking for a careful and enthusiastic
experimentalist, who is happy to discuss with
theoreticians with whom we collaborate and
to work as a part of an international team.
[1] S. Heitkam, Y. Yoshitake, F. Toquet, D.
Langevin, A. Salonen, PRL, 110, 178302
(2013)
Please, indicate which speciality(ies) seem(s) to be more adapted to the subject:
Condensed Matter Physics: YES
Quantum Physics:
NO
Macroscopic Physics and complexity: YES
Theoretical Physics:
NO