A novel parallel capillary-cavity model for the analysis of pneumatic hammer vibration in porous aerostatic bearings

Abstract

Porous aerostatic bearings (PABs) are widely used in high-speed applications and ultra-precision machinery owing to their frictionless motion and remarkable stability. In this paper, a novel parallel capillary-cavity model based on the intricate pore structure characteristics is established to characterize air flow in PABs and analyze the pneumatic hammer vibration. An experimental setup is constructed to measure the pneumatic hammer vibration of PABs. The experimental results exhibit a strong agreement with the predictions. The effects of various factors, including different loads, air pressures and porosities on the pneumatic hammer vibration are thoroughly discussed. The results show that higher air supply pressures, larger loads, and increased porosity are more likely to trigger pneumatic hammer vibration in PABs.