Sedimentation of a colloidal monolayer down an inclined plane

Brennan Sprinkle, Sam Wilken, Shake Karapetyan, Michio Tanaka, Zhe Chen, Joseph R. Cruise, Blaise Delmotte, Michelle M. Driscoll, Paul Chaikin, Aleksandar Donev

Research output: Contribution to journalArticlepeer-review

Abstract

We study the driven collective dynamics of a colloidal monolayer sedimenting down an inclined plane. The action of the gravity force parallel to the bottom wall creates a flow around each colloid, and the hydrodynamic interactions among the colloids accelerate the sedimentation as the local density increases. This leads to the creation of a universal "triangular"inhomogeneous density profile, with a traveling density shock at the leading front moving in the downhill direction. Unlike density shocks in a colloidal monolayer driven by applied torques rather than forces [Phys. Rev. Fluids 2, 092301(R) (2017)2469-990X10.1103/PhysRevFluids.2.092301], the density front during sedimentation remains stable over long periods of time even though it develops a roughness on the order of tens of particle diameters. Through experimental measurements and particle-based computer simulations, we find that the Burgers equation can model the density profile along the sedimentation direction as a function of time remarkably well, with a modest improvement if the nonlinear conservation law accounts for the sublinear dependence of the collective sedimentation velocity on density.

Original languageEnglish (US)
Article number034202
JournalPhysical Review Fluids
Volume6
Issue number3
DOIs
StatePublished - Mar 2021

ASJC Scopus subject areas

  • Computational Mechanics
  • Modeling and Simulation
  • Fluid Flow and Transfer Processes

Fingerprint Dive into the research topics of 'Sedimentation of a colloidal monolayer down an inclined plane'. Together they form a unique fingerprint.

Cite this