Study On The Performance Of The Aerostatic Bearing Of Variable Throttle Restrictor

Hydrostatic gas bearing has the advantages of high precision,low friction resistance and low pollution.It is widely used in precision mechanical equipment.Due to the characteristics of air will be affected by the outside world,the density and volume will change,This reduces the important characteristics of gas bearing and affects the development prospect of gas bearing.This article,the limit restrictor is used as the starting point and the hydrostatic gas bearing as the carrier.In order to improve performance,stiffness and working stability,Through the study of changing external structural parameters the influence on its static performance and the law of flow field change are analyzed,It also provide reference and theoretical support for the indepth research of hydrostatic gas bearing.The physical model of variable throttle hydrostatic gas bearing is established.Through the analysis of CFD numerical calculation model and coupling equation,different methods in gas-solid coupling and their basic solution processes are compared,the method suitable for solving the model of variable throttle hydrostatic gas bearing is determined,and the influence law of structural parameters on the static characteristics of bearing is preliminarily studied.The partition and local encryption method of the gas-solid coupling model are used,and the gas-solid coupling method is combined to study the static performance change law of the aerostatic gas bearing cavity thin plate overall system under different structural parameters.At the same time,The results show that due to the existence of pressure equalizing shallow cavity,it plays the role of gas accumulation and stable pressure,so as to effectively improve the performance of the bearing during operation.The air supply pressure is a factor to improve the static performance of the bearing,but the growth rate also slows down gradually.but the growth rate is also gradually slowed down.The increase of orifice diameter has a great impact on the bearing stiffness,and the air consumption also increases with the increase of orifice diameter.Thus,Before staring design and processing of bearings,the influence of various factors should be considered and the optimal parameters should be selected.The fluent and transient structure modules in ANSYS software are used for two-way gas-solid coupling simulation calculation to explore the influence curve of various factors of variable throttle hydrostatic gas bearing at dynamic time.The results show that when the load is applied for interference,the steady-state curve of the bearing fluctuates obviously first and then tends to be stable.With the increase of air supply pressure and the number of orifices,the fluctuation range of gas film during bearing operation can be effectively reduced,and the bearing capacity and stiffness at dynamic time can be improved.Increasing the pore size will lead to severe fluctuation of the working gas film and reduce the stability.Eddy current phenomenon will cause micro vibration when the bearing works.The variable throttle hydrostatic gas bearing is developed and processed,and the bearing bearing capacity and micro vibration test platform is built.The research results show that the variation trend of bearing capacity experimental value is basically consistent with that of gas-solid coupling simulation value.The micro vibration experimental results show that eddy current phenomenon will lead to micro vibration.By comparing the results of experiment and theoretical analysis,the correctness of theoretical analysis is verified.At the same time,the static and dynamic characteristics of variable throttle bearing are quantitatively analyzed.In this paper,the bearing performance,flow field characteristics and related experiments of variable throttle hydrostatic gas bearing are researched.The results show that the transition of velocity and flow field of variable throttle hydrostatic gas bearing is relatively stable,also has better performance,which can effectively expand the working scene.It has important guiding significance for enriching and perfecting the design of hydrostatic gas bearing and gas lubrication theory.