Elastohydrodynamic Lift at a Soft Wall

Phys Rev Lett. 2018 May 11;120(19):198001. doi: 10.1103/PhysRevLett.120.198001.

Abstract

We study experimentally the motion of nondeformable microbeads in a linear shear flow close to a wall bearing a thin and soft polymer layer. Combining microfluidics and 3D optical tracking, we demonstrate that the steady-state bead-to-surface distance increases with the flow strength. Moreover, such lift is shown to result from flow-induced deformations of the layer, in quantitative agreement with theoretical predictions from elastohydrodynamics. This study thus provides the first experimental evidence of "soft lubrication" at play at small scale, in a system relevant, for example, to the physics of blood microcirculation.

MeSH terms

  • Biomimetic Materials / chemistry*
  • Biotin / chemistry
  • Elasticity
  • Erythrocytes / chemistry*
  • Glycocalyx / chemistry*
  • Hydrodynamics
  • Microcirculation
  • Models, Biological
  • Models, Theoretical*
  • Streptavidin / chemistry

Substances

  • Biotin
  • Streptavidin