Study On Static Characteristics Of Microporous Static Pressure Gas Thrust Bearing

Air bearings are mainly divided into three types: static pressure,dynamic pressure and extrusion according to the working principle.Compared with traditional grease-lubricated bearings,air bearings have the advantages in principle.Their inherent frictionless,high speed,high precision and nontoxic The excellent performance such as no pollution makes air bearings widely used in ultra-precision and ultra-high-speed motion equipment,such as ultra-precision machine tools,air centrifugal compressors,and coordinate measuring instruments.But gas bearings also have shortcomings such as low stiffness,limited bearing capacity,and poor stability.These shortcomings limit the widespread use of gas bearings.In order to explore the working principle and dynamic and static characteristics of air bearings,domestic and foreign scholars have conducted extensive and in-depth research from the lubrication mechanism and bearing structure.In order to expand the use range and application field of air bearings,this paper has carried out research on the lubrication mechanism and static characteristics of air static pressure thrust bearings.This paper first establishes the structure diagram of the working principle of the air bearing based on the working principle of the air static pressure gas bearing,establishes the calculation coordinate system of the air static thrust bearing,and derives the Reynolds lubrication equation describing the pressure distribution of the working gas film of the air static thrust bearing,Based on the basic knowledge of fluid mechanics,conservation of mass,conservation of momentum,etc.and using the finite difference method and Newton iterative numerical solution method to solve the pressure distribution in the gas film,thereby further analyzing the static bearing capacity and static stiffness of the static pressure thrust bearing,through the analysis of the static characteristic parameters of the bearing,expounded the working principle of the static pressure thrust bearing and the influence of various parameters on the static characteristics of the bearing.Then the CFD(Computational Fluent Dynamics)software is used to simulate and analyze the bearing flow field.CFD is a computational fluid dynamics technology developed in the1980 s and is a branch of fluid mechanics.Using CFD software simulation can be more intuitivly and clearly study the distribution of the flow field inside the gas static pressure bearing,so that the performance of the bearing can be analyzed.First,use ICEM software to model and mesh the bearings to be studied and set basic boundary conditions,and then import it into the FLUENT solver,select the appropriate solution model and set reasonable solution settings,solve the model to obtain its flow Field distribution data,finally use FLUENT’s own post-processor or Post and other professional post-processor to analyze the obtained data.Then the above-mentioned lubrication theory and numerical analysis and bearing flow field simulation analysis were experimentally verified.By establishing an air static pressure thrust bearing static thermal test bench,the static characteristics of the bearing were tested and compared with the numerical value The results of analysis and fluid simulation are compared to verify the accuracy and rationality of the established mathematical model and numerical calculation method.It can also carry out actual tests and inspections on physical bearings,which provides a basis for the manufacture and inspection of bearings.