Performance Investigation of Micro-Orifice Restricted High-Speed Aerostatic Journal Bearings Based on the Finite Element Method

Advancements in manufacturing technology have facilitated the use of micro-orifice restrictors (MORs) in aerostatic bearings. However, the understanding of their effectiveness in journal bearings remains limited. This study utilizes FEM for solving the nonlinear Reynolds equation, incorporating velocity terms, to analyze the characteristics of aerostatic journal bearings (AJBs). The concepts of air impedance and pressure range are introduced and applied to explain the advantages of MORs over traditional orifice restrictors (TORs). Furthermore, the centrifugal deformation of the air film induced by high-speed operations and its consequential impact on bearing performance are methodically examined in detail. Finally, an experimental study is executed to confirm the proposed model and support the pertinent design principles. The experiment indicates that the air film thickness, accounting for centrifugal deformation, aligns more closely with the high-speed operating conditions characteristic of AJBs.