Partial surface texturing: A mechanism for local flow reconditioning in lubricated contacts

The texture hydrodynamics occurring in optimized steady-state lubricated contacts is theoretically investigated recurring to the recent Bruggeman texture hydrodynamics model. In particular, an attempt is made to unravel the intimate relationship between the texture-induced local flow properties and the macroscopic characteristics of the contact such as friction and supported load. The existence of different mechanisms of fluid flow harvesting and channeling is discussed, highlighting their strict relationship to the particular texture physical and topological properties. Whilst their single-species optimization does not produce particularly interesting performances in comparison to classical geometries, their optimized synergistic interaction, instead, provides a remarkable load generation and friction reduction almost independently from the macroscopic geometrical characteristics of the contact. The provided discussion can be easily extended to other contact geometries, such as for journal bearings, wet clutches and dynamic sealings, as well as to bio-tribology and soft contact applications.

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