Dynamic Analysis of a Cantilever-Mounted Gas-Lubricated Thrust Bearing

Abstract

The dynamic stability of a cantilever-mounted gas-lubricated thrust bearing is analyzed using the step-jump approach. The solution is based on linearization of the equations of motion assuming small perturbation about an equilibrium position. Stiffness and damping of the lubricating film are expressed analytically in terms of Laguerre coefficients thus, enabling a parametric investigation of the bearing. The general theory is used to examine an actual bearing design. It is found that the theoretical results agree with existing experimental data, in that, both show that the bearing is unstable at the design point and becomes more stable as speed decreases.