Air Foil Bearings - A Modeling Approach

M. Bezemer-Krijnen[1], Y.H. Wijnant[1], A. de Boer[1]
[1]University of Twente, Enschede, The Netherlands
Published in 2013

A first generation air foil bearing (AFB) is shown in Figure 1. AFBs induce, at higher rotating speeds, an air film between the journal and the top foil, which lowers the friction forces. The goal of this study is to develop a model of an AFB.

The thickness of the air film depends on the clearance, eccentricity and elastic deformations of the bump structure. The flow in the air film between top foil and journal can be described by a Lubrication Shell. The bump structure is modeled with a nonlinear spring foundation. The stiffness of the springs is implemented by a MATLAB function describing the stiffness of the springs as function of the deformation and the position of the springs.