Analysis of air foil thrust bearings with annular top foil including wear prediction, Part II: Experimental investigations

Considering air foil thrust bearings, usually a multi-pad design is used. Here, an alternative thrust bearing design with an annular-shaped top foil geometry is considered and investigated experimentally. For the experiments, a dedicated and specially designed high-precision test rig is used. The newly designed test rig allows high-speed measurements of different interesting bearing parameters for thrust loads up to 100 N and rotor speeds up to 120 krpm. In this work, a special focus concerns the wear occurring in the coating layer of the top foil. It will be shown that wear is significantly influencing the performance of this bearing type. Also, a comparison between the experimentally determined load capacity, power loss, and disk temperature with simulated data generated with a multi-physical TEHD model is given.