Experimental Static and Dynamic Characteristics of Multi-layer Gas Foil Thrust Bearing

Gas foil bearings are widely used in the field of national defence because of their advantages of high speed and low friction. In recent years, the multi-layer gas foil thrust bearing has attracted much attention due to its good environmental adaptability and greater deformation adaptability. This study systematically studied the influence of these factors including load, frequency and amplitude of excitation force, preload force and speed on the static and dynamic performance of bearings. In the experiment of exploring the static stiffness of bearing, the stiffness of bearing showed a nonlinear increasing trend with the increase of load. The reliability of the calculation method was verified from the time domain and frequency domain in the experiment without rotating, and the dynamic characteristics under different preload and vibration amplitude were analysed. In addition, the influence of different working conditions on energy dissipation was discussed by studying the change of hysteresis curve area. The experimental results showed that the stiffness and damping increase with the increase of preload and excitation force amplitude. As the frequency increased, the damping decreased, and the increase in frequency changed the phase of the hysteresis curve. The influence of gas film formation on bearing stiffness and damping was further discussed in the experiment with rotating. The experimental results showed that the stiffness and damping of bearing with gas film formation were lower than those without rotating because of the low gas viscosity, bearing capacity and damping. The research results of this study provided a valuable reference for optimizing the structure of multi-layer gas foil thrust bearings.