Paper: Particle entrapment in elliptical, elastohydrodynamic, rough contacts and the influence of intermolecular (van der Waals) forces.

Author: George K. Nikas

Published in: Proceedings of the Institution of Mechanical Engineers (IMechE), Part J: Journal of Engineering Tribology, 2021, 235(11), 2227-2246


The entrapment/rejection process of spherical, rigid micro-particles in elliptical, rough elastohydrodynamic contacts is modelled. An earlier model of the author is extended to include van-der-Waals intermolecular forces, in addition to mechanical (reaction and friction) and fluid-particle forces. Surface roughness effects are also introduced in terms of the intermolecular-force formulation and in the microscale-friction (particle-asperity) sub-model. Possibilities related to particle entry into a contact are quantified by weight factors and performance indices. A total entrapment index is defined and linked to the probability of particle entrapment. A parametric analysis investigates the effect of the intermolecular particle-force on the entrapment probability by varying the contact load, lubricant viscosity, elastic modulus of the contacting solids, contact velocity, and the macroscopic (Coulomb) friction coefficient.


Graphical abstract

Graphical abstract

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