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arXiv · 1912.02617

Lift induced by slip inhomogeneities in lubricated contacts

Aidan Rinehart·Uǧis L{ā}cis·Thomas Salez·Shervin Bagheri
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Abstract

Lubrication forces depend to a high degree on elasticity, texture, charge, chemistry, and temperature of the interacting surfaces. Therefore, by appropriately designing surface properties, we may tailor lubrication forces to reduce friction, adhesion and wear between sliding surfaces or control repulsion, assembly, and collision of interacting particles. Here, we show that variations of slippage on one of the contacting surfaces induce a lift force. We demonstrate the consequences of this force on the mobility of a cylinder traveling near a wall and show the emergence of particle oscillation and migration that would not otherwise occur in the Stokes flow regime.Our study has implications for understanding how inhomogeneous biological interfaces interact with their environment; it also reveals a new method of patterning surfaces for controlling the motion of nearby particles.

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Aidan Rinehart, Uǧis L{ā}cis, Thomas Salez, Shervin Bagheri. 2020-04-30. Lift induced by slip inhomogeneities in lubricated contacts. https://doi.org/10.1103/physrevfluids.5.082001

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