Air foil thrust bearings with top foil sagging: Theoretical predictions and experiments

Some degree of top foil sagging is inevitable for air foil thrust bearings without bump foils support in taper region. This paper aims at revealing the effect of top foil sagging on static performance of the bearings. The nonlinear stiffness of bump foil was considered in theoretical calculations and static characteristics of bearings with varying degrees of foil depression were obtained. Moreover, a bearing test rig was designed to measure the deflection of top foil and friction torque. An excellent correspondence between theoretical and experimental results was found. The results presented in this study can offer advice for designing bearings with diminishing the influence of sagging on the bearing performance.

Automated summary

This paper aims to investigate the effect of top foil sagging on the static performance of air foil thrust bearings. The study considers the nonlinearity of bump foil stiffness and obtains the static characteristics of bearings with different degrees of foil depression. Experimental results match well with theoretical calculations. The findings provide guidance for designing bearings that minimize the influence of sagging on performance.