General analyses are developed to predict the role of surface roughness, rarefaction effects, and various operating parameters in thin-film gas lubrication. Both shear- and squeeze-film effects are considered. The squeeze-film analysis is developed for transient and periodic motions. The analyses are based on average flow (roughness) factors. The results are presented in terms of Knudsen number, h/σ (film thickness/standard deviations of composite roughness) and roughness-orientation parameters. The appropriate analyses presented in this paper are simple and can be applied to magnetic recording and other applications to provide design guidelines.

This content is only available via PDF.
You do not currently have access to this content.