For a hard disk drive operating in a humid environment, the water vapor in the slider’s air bearing is typically compressed beyond its saturation vapor pressure, causing the vapor to condense. Consequently, the air bearing pressure decreases and the slider’s flying attitude adjusts to balance the forces from the suspension. A method for calculating this air bearing response to humid air is presented. Using two air bearing designs, several test cases are analyzed to illustrate the air bearing response for various temperatures and humidity levels. The calculated flying heights agree with those measured in commercial hard disk drives.
Issue Section:
Research Papers
Keywords:
hard disk drive,
air bearing,
flying height,
pressure,
humidity,
temperature,
disc drives,
hard discs,
humidity,
machine bearings
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.Copyright © 2008
by American Society of Mechanical Engineers
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