Abstract
This paper introduces the dynamic characteristic analysis model of the bump type gas foil bearing. The analysis model is capable of analyzing the interaction between the components and the thin working fluid film based on fluid-structure interaction finite element method when the bearing is operating. In order to make it, researchers can analyze the effect of different bearing foil structure equivalent stiffnesses on bearing operating characteristics, such as the pressure and temperature distribution patterns in the working fluid film, stiffness and damping coefficient of the bearing, etc. The top and bump foils in the foil structure of bearing are modeled as an infinite number of Hookean springs attached to the stiff wall of the housing while the hydrodynamic pressure distributions exerting on the springs are modeled as gas film working in steady state lubrication condition. The complete three dimensional multiphysics model built by commercial computer-aided engineering package, which can do the calculation based on finite element method independently for the fluid and solid domain. After that, the model can transfer the analysis results to each other at the interface between those models to do the simulation until the system reaches a quasi-steady state. Some environment states of bearing during operation will be set as the boundary condition and input to the model. The results of the simulation model are in good agreement with the experimental results of published research papers. In order to verify the various operating characteristics of the bearings and compare the results with the analytical model in the future, an internal experimental test bench has been established also. That test bench has the ability to confirm the working characteristics of bearings at different speeds and bearing loads.