Coupled effects of Random Surface Roughness and Slip Flow on The Gas-lubricated Micro Spherical Spiral Groove Bearings

10.6567/IFToMM.14TH.WC.PS18.002

K. Feng；W. J. Li

micro system ； spherical spiral groove gas bearings ； slip flow ； surface roughness

Proceedings of the 14th IFToMM World Congress

14th-5（2015 / 11 / 06）

491 - 497

英文

The performance of a gas lubricated micro spherical spiral groove bearing is investigated. The random bearing surface is characterized by the fractal geometry. The Weierstrass-Mandelbrot(W-M) function is presented to describe the self-affine roughness. A modified Reynolds equation is formed by incorporating with Wu’s slip flow boundary condition to simulate the rarefaction lubrication characteristics. The coordinates is firstly transformed and then the Reynolds equation is numerical solved by using finite different method (FDM) with Green's theorem incorporated. The effects of groove roughness and slip flow incorporated with different groove depth on the complex bearing characteristics are investigated and discussed. The results indicate that roughness and the slip flow have significant influences on the performance of gas bearing.