The numerical calculation of static performance of multi wound foil bearing and experimental validation

Multi wound foil bearings (MWFB), as a kind of foil bearings with simple structures, 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. 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 the calculations, static characteristics of MWFB such as film thickness, load capacity and torque are presented. Finally, an experimental apparatus is built up to measure the load of MWFB at different operation condition, which are used to validate numerical calculation results.