For a particle entrained in an air bearing, various forces, such as the viscous drag force, Saffmann and Magnus lift forces and gravity force, will act on it. Such particles may pass through the air bearing or impact the slider or disk and then adhere to the surface or bounce off. In this paper, particle flow in an air bearing is simulated. The contamination of particles on a slider’s surface is analyzed using the assumption of adhesion upon impact. The effect of particle size and density on particle paths in the air bearing is studied. The numerical results show that particles are likely to contaminate slider surfaces in the transition regions on the rails. The density of the particles and the pitch angle of the slider are also found to strongly affect the flying path of the particles, and therefore, the accumulation of the particles on slider surfaces.

Issue Section:
Technical Papers
Keywords:
machine bearings, disc drives, hard discs, confined flow, two-phase flow, laminar flow, surface contamination, adhesion, impact (mechanical)
Topics:
Air bearings, Contamination, Disks, Particle flow, Particulate matter, Density, Rails
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