The pressure drop effect of aerostatic bearing with orifice restrictors will reduce the bearing capacity.In order to explore the influence of different bearing structural parameters on the pressure drop effect at the orifice outlet,taking the aerostatic bearing with orifice restrictors as the research object,the finite difference method and the super relaxation iteration method were used to calculate the gas film flow field of the bearing,and the gas film pressure distribution under different bearing structural parameters was obtained.The results show that the orifice diameter and number,eccentricity,orifice position and average gas film thickness have an important influence on the pressure drop effect of the orifice.The pressure drop effect decreases with the increase of orifice diameter and number,and increases with the increase of average gas film thickness and eccentricity,and decreases with the increase of air temperature.The closer the orifice is to the bearing end face,the stronger the pressure drop effect is.The change of rotating speed basically has no effect on the pressure drop of the orifice,indicating that the pressure drop effect is mainly related to the static characteristics of the bearing and has little relationship with the dynamic performance.