Foil bearings are supposed to be one of the best candidates of supporting component for turbo-machineries because of their design simplicity, reduced weight and size, high speed and temperature capability, and easy maintenance. Among various types of foil bearings, multi wound foil bearing (MWFB), which had been designed and fabricated in our lab, is easy to analyze static characteristics even though load capability of which is small compared with other types of foil bearings.
In this study, a theoretical model of MWFB taking account of the effect of the foil deformation is developed to predict its static performance. Reynolds equation is solved using Finite Difference Method (FDM) to yield air pressure distribution, while the elastic deformation equation is solved by Finite Element Method (FEM) to predict the deformation of the foil. Then, the above two equations are coupled by several iterations until the convergence criterion is reached. Based on such calculations, static characteristics of MWFB such as load capacity, torque are presented.