Stability and dynamics of an orifice based aerostatic bearing with a compliant back plate. (October 2019)

• Record Type: Journal Article
• Authors: Maamari, N.; Krebs, A.; Weikert, S.; Wild, H.; Wegener, K.
• Is Part Of: Tribology international. Volume 138(2019)
• Page Start: 279
• Page End: 296
• Publication Date: 2019-10
• Subjects: Aerostatic bearing -- Conicity compliance -- Dynamic response -- Damping coefficient -- Pneumatic hammering; Tribology -- Periodicals; 621.89
• DOI: 10.1016/j.triboint.2019.05.047
• Languages: English
• ISSNs: 0301-679X

Abstract

Abstract: Aerostatic bearings are extensively used in precision machines. The dynamic performance of aerostatic bearings is limited by the inherent compromise between stiffness and damping. To enhance their performance, the bearing surface is made compliant to the pressure distribution, leading to high static stiffness. To investigate the damping characteristics of bearings with structural compliance, this work presents a dynamic model encapsulating the fluid-structure interaction. Experimental analysis validated the model and a sensitivity analysis established a design guideline ensuring high stiffness and positive damping. The findings reported an increase by a factor of three in stiffness compared to conventional bearing while ensuring a positive damping. Highlights: Dynamic model of a new type of aerostatic bearing encapsulating fluid-structural interaction. Experimental analysis on the dynamic response of aerostatic bearing with compliant back plate. CFD model to extract coefficient of discharge for orifice-based bearing with convergent gap. Simplified lumped model illustrating the dilemma between stiffness and damping.