A novel micro-vibration prediction method for an aerostatic thrust bearing by using Ω-vortex identification

In this paper, an Ω-vortex identification method is proposed to predict the micro-vibration of an aerostatic thrust bearing. It can identify vortex structure and corresponding spatial distribution in bearing gas film accurately, quantifying vortex region area by the Ω iso-surface. Four methods are used to predict the micro-vibration of nine aerostatic thrust bearings according to the flow fields obtained by large eddy simulation (LES). The experimental results indicate that the prediction accuracy is 66.7% for the maximum gas flow velocity method, 83.3% for the maximum gas pressure difference method and gas pressure fluctuation method, and 100% for the Ω-vortex identification method. The proposed method is helpful for micro-vibration prediction and provides guidance for structure optimization to suppress vortex and micro-vibration of an aerostatic thrust bearing.