Research On Flow Field Characteristics Of Clearance Oil Film In Hydrostatic Thrust Bearings

With the continuous rapid development of modern machinery manufacturing and processing industry,from the global index of Large-scale CNC machining equipment,Large-scale CNC machining equipment for its machine workbench load capacity,stable performance,processing efficiency and processing accuracy requirements are becoming higher and higher.Hydrostatic thrust bearing,as a key component of large-scale CNC machining equipment,consists of three parts:rotating table,clearance oil film and base.In order to improve the working stability and load-carrying performance of hydrostatic thrust bearing,reduce friction loss and prolong service life,it is very important to research flow field characteristics of clearance oil film in hydrostatic thrust bearingsThe control flow equation,bearing capacity equation,temperature rise equation,oil film thickness with load and speed matching equation and other related governing equations of oil film flow field characteristics are derived based on the principles of fluid mechanics and tribology in double rectangular cavity,circular cavity and racetrack cavity.The viscosity-temperature relationship of five types of hydraulic oil is fitted by using MATLAB,and the viscosity-temperature relation equation is deduced.The 3D geometric modeling of the oil film model of double rectangular cavity,circular cavity and racetrack cavity are carried out by using Solid Works,and the models are imported into ICEM-CFD for mesh division,and the boundary conditions are set by using FLUENT,and the flow field characteristics of variable viscosity clearance oil film is solved.The effects of cavity depth,rotational speed,load and hydraulic oil viscosity on the oil film flow characteristics are discussed in double rectangular cavity,circular cavity and racetrack cavity,and the temperature and pressure characteristics of the clearance oil film are analyzed based on the flow characteristics.It provides a theoretical basis for the selection of cavity structure parameters,the selection of hydraulic oil viscosity and the optimization of oil cavity structure of hydrostatic thrust bearing in engineering practice.The new type high-speed heavy-duty hydrostatic thrust bearing test table with Q1-224 is used to investigate experiments on the temperature and pressure characteristics of the clearance oil film of the double rectangular cavity,and the experimental data and simulation results will be compared.The correctness of the simulation results of the temperature characteristics and pressure characteristics of the clearance oil film are verified,and the feasibility and correctness of the numerical simulation method are proved.