The structure optimization of aerostatic bearings with radial wedge grooves to improve static Performance: Theoretical predictions and experimental measurements

Abstract

Aerostatic bearings play a vital role as a fundamental support component in ultra-precision manufacturing and measuring equipment. However, due to the air compressibility, the loading capacity and stiffness of aerostatic bearings are lower than that of traditional bearings, which limits their application in high-precision manufacturing fields. This study introduced a novel design of aerostatic bearing with radial wedge grooves (RWG) aimed at enhancing static performance. The influence of RWG structural factors on the static performance of aerostatic bearings was examined using computational fluid dynamics (CFD). Three-dimensional large eddy simulation (LES) methods were used to examine the transient flow properties of aerostatic bearings with three distinct structures. To confirm the correctness and validity of the CFD model, experimental measurements of the static performance and micro-vibration in aerostatic bearings with three different wedge groove structures were carried out. The results revealed that the loading capacity of aerostatic bearings with RWG gradually increased with the increase of the groove radial angle θ and groove wedge angle γ, exhibiting an initial rise followed by a subsequent decrease with an increase in groove radius. Furthermore, the stiffness of aerostatic bearings demonstrated progressive improvement with an increase in wedge groove radius, groove radial angle and groove wedge angle. The mass flow rate of aerostatic bearings shows an increase as the wedge groove radius, groove radial angle, and groove wedge angle are increased. This study presents new insights into the application of aerostatic bearing in grooves throttling.