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arXiv · 2306.17694

Gap-Dependent Hydrodynamic Lubrication in Conformal Contacts

James A. Richards·Patrick B. Warren·Wilson C. K. Poon
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Abstract

We show that the hydrodynamic lubrication of contacting conformal surfaces with a typical texture height gives rise to a universal behaviour in the Stribeck curve in which the friction coefficient shows an anomalous power-law dependence on the Sommerfeld number, $μ\sim S^{2/3}$. When the gap height drops below the `texture length scale', deviations from $S^{2/3}$ occur, which may resemble the onset of elasto-hydrodynamic and mixed lubrication. Within this framework, we analyse literature data for oral processing and find $S^{2/3}$ scaling with deviations consistent with measured lengthscales.

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James A. Richards, Patrick B. Warren, Wilson C. K. Poon. 2023-06-30. Gap-Dependent Hydrodynamic Lubrication in Conformal Contacts. https://arxiv.org/abs/2306.17694

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