Experimental Analysis of Cylindrical Air-Bearing Dynamic Coefficients

• Published in: Tribology transactions Vol. 53; no. 3; pp. 329 - 339
• Main Authors: Matta, P., Arghir, M., Bonneau, O.
• Format: Journal Article
• Language: English
• Published: Philadelphia, PA Taylor & Francis Group 01.05.2010; Taylor & Francis; Taylor & Francis Inc
• Subjects: Aerodynamics; Air Bearings; Applied sciences; Bearing; Bearings; Bearings, bushings, rolling bearings; Comparative analysis; Drives; Dynamic characteristics; Dynamic Modelling; Dynamics; Exact sciences and technology; Excitation; Friction, wear, lubrication; Loads (forces); Machine components; Mechanical engineering. Machine design; Representations; Shakers; Transfer functions; Tribology; Static characteristic; Dynamic characteristic; Aerodynamics; Mechanical clearance; Gas bearing; Experimental study; Spring; Air Bearings; Hydrodynamic lubrication; Dynamic Modelling; Hydrostatic lubrication; Shaft; Hybrid bearing; Transfer function; Dynamic model; Floating body; Tribology
• ISSN: 1040-2004; 1547-397X
• DOI: 10.1080/10402000903283318

The present work contains a detailed presentation of a test rig for measuring the static and dynamic characteristics of air bearings. The test rig consists of a 60-krpm spindle entraining a shaft guided by a Lomakin hybrid bearing. The test bearing is floating, overhung at one end of the shaft, and mounted on a squirrel cage. The bearing is statically loaded by a spring, and the dynamic excitation is applied by two shakers. Frequency-dependent dynamic coefficients are identified by sweeping the allowable excitation frequencies and by using a transfer function representation of the complex impedances. Test results are presented and compared with theoretical predictions for a cylindrical aerodynamic bearing of 30-mm diameter, L/D = 1, and 22-μm clearance.