Static Characteristics of Gas-Lubricated Slider Bearings Operating in a Helium-Air Mixture

Abstract

This paper outlines experimental investigations of the static characteristics of self-acting gas-lubricated slider bearings operating in a helium-air mixture. The experimental results are compared with numerical results obtained by solving a modified Reynolds equation and a generalized lubrication equation based on an equivalent molecular mean free path (MMFP) and on an equivalent viscosity derived from molecular gas dynamics. At any mole ratio of air α, the values of the equivalent MMFP are generally expected to be smaller than those of the MMFP derived from linear interpolation, whereas the values of equivalent viscosity are expected to be larger. The numerical results agree well with the experimental results within the range of α from 1.0 to 0.6. Lower values of α give a bigger difference between numerical and experimental results, and make the experimental results lower than the numerical results. Moreover, results of a generalized lubrication equation based on the Boltzmann equation give a closer prediction or qualitative tendency to the experimental results than do those based on the modified Reynolds equation.