The Finite Element simulation of the multi-leaf foil journal bearings with Large assembly preload

Abstract

Gas Foil Bearings (GFBs) are a proven alternative to rolling element bearings for high speed applications. In order to supplies much higher damping and much bigger load capacity, the Large assembly preload is often added in GFBs now, especially in the multi-leaf foil bearings. According to the structure characteristics of the multi-leaf foil journal bearing with large assembly preload, the nonlinear Contact Finite Element model of is established through introducing the assistant simulation parts. The assistant simulation parts were used to help form the last contact relationship of foil bearings in the numerical simulation process. Through modifying the moving contact relationship between the foil bearing parts in the different simulation phase, the large assembly preload of foil bearing was dealt with using the nonlinear contact Finite Element analysis between rigid bodies and flexible bodies. The object of the analysis exhibit the feasibility of method using assistant simulation parts and rigid-flexible bodies contact algorithm to simulate the large assembly preload multi-leaf foil bearings. The rigid-flexible bodies contact algorithm is the theory base for dealing with this kind of problem and the moving rigid contact bodies is the key to dealing with this kind of problem. In this paper, a typical five leaves foil bearing with large preload effect was analyzed as a successful case to prove the analysis feasibility and accuracy.