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Self-sustained lift and low friction via soft lubrication.

ABSTRACT: Relative motion between soft wet solids arises in a number of applications in natural and artificial settings, and invariably couples elastic deformation fluid flow. We explore this in a minimal setting by considering a fluid-immersed negatively buoyant cylinder moving along a soft inclined wall. Our experiments show that there is an emergent robust steady-state sliding regime of the cylinder with an effective friction that is significantly reduced relative to that of rigid fluid-lubricated contacts. A simple scaling approach that couples the cylinder-induced flow to substrate deformation allows us to explain the elastohydrodynamic lift that underlies the self-sustained lubricated motion of the cylinder, consistent with recent theoretical predictions. Our results suggest an explanation for a range of effects such as reduced wear in animal joints and long-runout landslides, and can be couched as a design principle for low-friction interfaces.

SUBMITTER: Saintyves B

PROVIDER: S-EPMC4889378 | biostudies-literature | 2016 May

REPOSITORIES: biostudies-literature

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Self-sustained lift and low friction via soft lubrication.

Saintyves Baudouin B Jules Theo T Salez Thomas T Mahadevan L L

Proceedings of the National Academy of Sciences of the United States of America 20160509 21

Relative motion between soft wet solids arises in a number of applications in natural and artificial settings, and invariably couples elastic deformation fluid flow. We explore this in a minimal setting by considering a fluid-immersed negatively buoyant cylinder moving along a soft inclined wall. Our experiments show that there is an emergent robust steady-state sliding regime of the cylinder with an effective friction that is significantly reduced relative to that of rigid fluid-lubricated cont ...[more]

PMID: 27162361

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