For some complex slider designs the two dimensional approximation incorporated in the Reynolds equation for determining the airflow in the air bearing is not applicable due to steps in the air bearing surface. A model that incorporates some transverse flow effects is needed to better characterize the airflow between the slider and disk for some applications. In this paper such a model is derived to better predict the paths of contamination particles entrained in the air bearing. The characteristics of airflow and particle flow within the air bearing are then studied. The analysis including the transverse effects reveals that the transverse velocity of the air is not negligible in the geometric transition regions of the slider. This transverse velocity has a significant effect on the flight path of particles, and therefore, on the particle contamination profile on slider surfaces. The assumption of adhesion of the particles upon impact with a surface is used as the contamination criteria, and it is viewed as the worst-case scenario.

Issue Section:
Research Papers
Keywords:
contamination, adhesion, fluid dynamics, approximation theory, multiphase flow, magnetic recording
Topics:
Air bearings, Contamination, Disks, Flow (Dynamics), Particle flow, Particulate matter, Lift (Fluid dynamics), Air flow, Drag (Fluid dynamics)
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