Load capacity of aerodynamic foil thrust bearings supported by viscoelastic material

Abstract

In recent years aerodynamic bump foil bearings have attracted considerable attention for the field of oil-free turbomachines. However, the shape of the bump foils is usually very complicated and the manufacturing of these bump foils is very troublesome. Moreover, in foil bearings applied to turbomachines, such as compressors and blowers, it is not necessary to use flexible supports made of metals because the operating temperature does not rise much. Therefore, in this article, two types of taper-land foil thrust bearings supported by viscoelastic material are proposed for easier manufacturing of foil bearings. In this work the load capacity of the proposed foil bearings experimentally and numerically was investigated. It was confirmed that the proposed bearings could be easily manufactured and operate well as aerodynamic thrust bearings. In addition, it was found that inserting a metal plate between the top foil and the viscoelastic support at the land region could improve the load capacity, and that the load capacity of the proposed foil bearing reached 160 N at 20 000 r/min.