Research On Air Bearing Capability Based Porous Integrated Restrictor

Air bearing has high precision,no pollution,long life,stable work,small friction and no fever phenomenon,is used in many areas.At the same time,the bearing capacity is poor,the stiffness difference and other factors are all the time limit its use.Therefore,domestic and foreign experts and scholars on the air bearing in-depth study,many design schemes are put forward and a lot of theoretical achievements are obtained.So that air bearing capability gradually improved.In this paper,a new type of restrictor composed of multiple orifice is designed,which is called a porous integrated restrictor,and the capability of air bearing with this new type of restrictor is studied.Firstly,the working principle,advantages and disadvantages of air bearing and the research status at home and abroad are introduced.Secondly,the gas control equation is deduced according to the Navier-Stokes equation,the finite difference method is used to discretize the governing equations of gas lubrication.The discrete governing equations are solved numerically by using the MATLAB software,obtain the bearing capacity and stiffness of the air bearing with a circular porous integrated restrictor.Compared with the traditional single-hole throttle air bearings,in the same throttle area,the porous integrated throttle of the air bearing has better bearing capacity and stiffness;The greater the number of orifice holes in the porous integrated restrictor,the greater the bearing capacity of the air bearing.Using a new algorithm get the pressure distribution in the air film of the rectangular porous integrated throttle bearing with a pressure equalizing groove are analyzed.Through the analysis of the calculation results:when the air film is small,the pressure tank has a good effect of maintaining the gas pressure,can improving the bearing capacity of the air bearing.Then the flow field at the outlet of the orifice is simulated by FLUENT software,the minimum value of the orifice outlet pressure is located at the outer edge of the orifice;the pressure value of the film increases rapidly with the increase of the radius,and then decreases rapidly and finally decreases linearly;the pressure are difference between the upper and lower surfaces of the gas film at the orifice outlet,The smaller the gas film clearance is,the closer the pressure value of the upper and lower surfaces tends to the same distance from the center of the orifice;the size of the cyclone at the outlet of the orifice and the decrease in the pressure on the upper surface of the film are proportional to the gap between the membranes.Provide the basis for the subsequent design of integrated porous restrictor.Finally,a reasonable experimental scheme is designed to test the bearing capacity of the air bearing with various types of integrated throttle by using the existing experimental equipment,proves the reliability of the theoretical analysis method used in this paper by compared experimental results with the theoretical results.