In order to study the wall erosion caused by fine particles during the running of air bearing,a dynamic and static air bearing model was established by means of three-dimensional modeling tool.Based on the continuum equation,the compressible fluid lubrication equation and the gas state equation,the steady gas lubrication Reynolds equation at isothermal condition was obtained.Combining with the discrete phase model (DPM) particle balance equation,the trajectory of particle motion and the maximum erosion rate of particles on the wall were analyzed.With the help of Fluent simulation software,the influence of gas pressure,spindle speed and particle size on the wall erosion of gas bearing was analyzed.The results show that with the increase of particle size,the wall erosion wear rate increases first and then decreases under the same operating conditions.The area of wall erosion wear increases with the increase of spindle speed,however,the maximum wall erosion wear rate is decreasing,and the wall wear area extends to the direction of spindle rotation.