We address the numerical modeling of roughness or texture effects in ultra-thin gas films. Rarefaction (high Knudsen number) effects are dealt with using the Generalized Reynolds Equation, and a homogenization procedure is proposed to rigorously account for arbitrary roughness/texture shapes. The presentation is focused on head-disk magnetic storage devices, but the techniques proposed are general. Some details of the implementation, along with numerical tests, are included. By removing the small space and time scales from the problem, the methodology allows for efficient modeling of slider bearings with small-scale features.

Issue Section:
Technical Papers
Keywords:
Knudsen flow, magnetic disc storage, finite element analysis, thin films, texture, film flow, lubrication
Topics:
Disks, Finite element methods, Resolution (Optics), Surface roughness, Texture (Materials), Finite element analysis, Knudsen number, Lubrication, Shapes, Pressure
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 by ASME
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