Novel full‐region model of inherent orifice aerostatic bearings considering air flow in orifice and clearance

Abstract

AbstractThe performance of inherent orifice‐restricted aerostatic bearings (IORABs) is directly determined by the coupling of air flow in the orifice and clearance. This paper presents a novel full‐region model to analyse the performance of IORABs. The air flowing in the orifice is treated to be adiabatic. The air flow in the pressure depression region of the clearance, which is the key factor influencing the bearing performance, including inertial and viscous terms, is modelled. The Reynolds equation is used to simulate the air flow in the laminar flow region of the clearance. By using this model, the pressure distribution, including the pressure depression characteristics, could be accurately predicted and achieved substantial agreement with the experimental results. The predicted load capacity is accorded well with the published experimental data without relying on the discharge coefficients. The airflow characteristics in the orifice are crucial in determining the bearing performance and directly influenced by the orifice inner surface shape (OISS). Therefore, the pressure distribution and the static characteristics of the bearings with coupling different OISS are also systematically analysed by using this model. Narrowing and widening OISS influence the pressure depression region and the pressure value of the turning point to directly influence the static characteristics of the bearings. The full‐region model and the results are significantly for guiding the precisely calculating and designing the IORABs.