Design, analysis, and implementation of a compound restrictor aerostatic bearing system

Abstract

Aerostatic bearings are the key components for ultra-precision instruments. In this paper, a novel compound restrictor aerostatic bearing that combines orifice, radial groove, and circumferential groove restrictors was proposed and prototyped. This innovative combination addresses the inherent limitations of conventional orifice restrictor bearings, such as vortex-induced micro-vibrations and reduced stability, by significantly enhancing both load capacity and stiffness. Analytical and CFD models are developed based on classical lubrication theory and laminar flow conditions. The designed bearing is studied through numerical and computational fluid dynamics (CFD) methods. Experiments on bearing load capacity and stiffness have been conducted to evaluate the performance. The results indicate that the load capacity and stiffness of the compound restrictor aerostatic bearing are enhanced by more than 51 % and 55 %, respectively, compared to those of the bearing with an orifice restrictor of the same dimensional parameters. This demonstrates the feasibility and effectiveness of the proposed compound restrictor aerostatic bearing, offering improved stability and reduced micro-vibrations compared to conventional designs.