Dynamic Characteristics of a Single Orifice Aerostatic Thrust Bearing with Nonlinear Spring Model of Air Film

Aerostatic bearings are widely used in ultra-precision machining equipment and measurement equipment due to their extremely high accuracy. However, they are more susceptible to resonance problems than liquid film bearings. Utilization of static stiffness of the air film for the calculation of resonance frequency and response of the bearing system represents a simple method but fails to capture the nonlinearity present in the static characteristics. This paper aims at presenting the dynamic characteristics of the bearing system by modelling the air film as a nonlinear spring. This modelling has the advantage of a simple and an effective procedure, accurately representing the nonlinearity in the static characteristics of the bearing system. The dynamic characteristics are determined by both theoretical and experimental methods and the corresponding results are compared with each other.