Inertial focusing of finite-size particles in microchannels

Evgeny S. Asmolov, Alexander L. Dubov, Tatiana V. Nizkaya, Jens Harting, Olga I. Vinogradova

Research output: Contribution to journalArticleAcademicpeer-review

13 Citations (Scopus)
153 Downloads (Pure)


At finite Reynolds numbers, Re, particles migrate across laminar flow streamlines to their equilibrium positions in microchannels. This migration is attributed to a lift force, and the balance between this lift and gravity determines the location of particles in channels. Here we demonstrate that velocity of finite-size particles located near a channel wall differs significantly from that of an undisturbed flow, and that their equilibrium position depends on this, referred to as slip velocity, difference. We then present theoretical arguments, which allow us to generalize expressions for a lift force, originally suggested for some limiting cases and Re ≤ 1, to finite-size particles in a channel flow at Re ≤ 20. Our theoretical model, validated by lattice Boltzmann simulations, provides considerable insight into inertial migration of finite-size particles in a microchannel and suggests some novel microfluidic approaches to separate them by size or density at a moderate Re.

Original languageEnglish
Pages (from-to)613-630
Number of pages18
JournalJournal of Fluid Mechanics
Publication statusPublished - 10 Apr 2018


  • microfluidics
  • particle/fluid flow
  • suspensions

Fingerprint Dive into the research topics of 'Inertial focusing of finite-size particles in microchannels'. Together they form a unique fingerprint.

  • Cite this

    Asmolov, E. S., Dubov, A. L., Nizkaya, T. V., Harting, J., & Vinogradova, O. I. (2018). Inertial focusing of finite-size particles in microchannels. Journal of Fluid Mechanics, 840, 613-630.