Boundary Conditions for Elastohydrodynamics of Circular Point Contacts

Mohammadpour, M., Johns-Rahnejat, Patricia orcid iconORCID: 0000-0003-2490-8753, Rahnejat, Homer orcid iconORCID: 0000-0003-2257-7102 and Gohar, R. (2014) Boundary Conditions for Elastohydrodynamics of Circular Point Contacts. Tribology Letters, 53 (1). pp. 107-118. ISSN 1023-8883

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The paper presents the solution of an elastohydrodynamic point contact condition using inlet and outlet lubricant entrainment with partial counter-flow. The inlet and outlet boundaries are determined using potential flow analysis for the pure rolling of contiguous surfaces. This shows that Swift–Stieber boundary conditions best conform to the observed partial counter-flow at the inlet conjunction, satisfying the compatibility condition. For the outlet region, the same is true when Prandtl–Hopkins boundary conditions are employed. Using these boundary conditions, the predictions conform closely to the measured pressure distribution using a deposited pressure-sensitive micro-transducer in a ball-to-flat race contact. Furthermore, the predicted conjunctional shape closely conforms to the often observed characteristic keyhole conjunction through optical interferometry. The combined numerical–experimental analysis with realistic boundary conditions described here has not hitherto been reported in the literature.

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