Study On The Dynamic And Static Performance Of A Small Gap Slot-restricted Throttle Thrust Bearing Based On Finite Element Method

Gas lubricated bearings are widely used in aerospace,precision and ultra precision machining.With the development of science and technology,engineering practice requires increasingly demanding static and dynamic characteristics of the bearing capacity and stiffness of gas lubricated bearing,therefore,the improvement of capacity,stiffness and other characteristics of the bearings has become the main research content in the field of precision machining.Usually the gas film thickness of gas lubrication bearing is from 20 ?m to 50 ?m,which is mainly due to the limitation of surface processing technology.Nowadays,with the rapid development of precision machining technology and the increasing appearance of new processing means and methods,precision machining capabilities are also constantly upgrading.Now the surface machining technology has been able to meet the requirements of the machining accuracy of the gas lubricated bearing under the small gap.In this paper,the static and dynamic characteristics of the throttle thrust bearing under the small gap will be studied.Firstly,establish a mathematical model of the slit throttling static pressure gas lubricated thrust bearing,and analyse the finite element method in detail to calculate the Reynolds equation of gas lubrication;Secondly,adopt the finite element method to solve the Reynolds equation of steady state gas lubrication,calculate the static bearing capacity and the static stiffness of the slit throttling static pressure gas lubricated thrust bearing through the integral operation,analyse the influence of the slit structure on the static performance parameters of the gas bearing,and provide the optimum range of the slit structure as well;Thirdly,based on the pressure distribution in the gas film,solve the Reynolds equation by using the perturbation method and the Galerkin method,work out the dynamic pressure distribution of the bearing gas film,and then work out the dynamic damping coefficient and dynamic stiffness coefficient of the bearing as well as analyse the influence of slit structure on the dynamic performance parameters of gas bearing.Finally,on the basis of ample theoretical analysis and numerical calculation,experiment and study the static performance of a disc type slit throttling static gas lubricated thrust bearing with a radius of 25 mm,the slit number of 8,slit the center angle of 30 degrees,test the accuracy and reliability of numerical results and test the correctness of the dynamic performance analysis method indirectly according to the grounding.The study results of this paper have certain guiding significance to the design,optimization and application of the small gap slit throttling static pressure gas lubricated bearing.