Study On Oil Film Bearing Characteristics Of Variable Stiffness Bearing Of Heavy Hydrostatic Thrust Bearing Based On Fluid-structure Interaction

The performance of the static thrust bearing,the primary rotating component in heavy-duty CNC equipment,is crucial to preserving the stability of machine tool operation.The oil film’s temperature field and pressure field will alter somewhat when the hydrostatic thrust bearing is operating.The solid domain of the bearing will deform to some amount when temperature and pressure are coupled,which will eventually cause the oil film’s morphology to change.In extreme working conditions,friction failure phenomena may also happen.Exploring the deformation law of the oil film and solid domain in the running process of bearings,as well as the impact of oil film deformation on bearing lubrication characteristics,is therefore of certain practical value.This study used the Q1-205 hydrostatic thrust bearing as the research subject to examine how different rotating speeds affected the solid domain deformation,oil film shape,and oil film lubrication characteristics under 0t and 8t loads.The following are the primary research findings: Based on the principle of hydrostatic support,the theory of computational fluid mechanics,heat transfer,and elastoplastic theory,the mathematical model of the hydrostatic thrust bearing system is developed,and a nonlinear relationship between the stiffness of the variable stiffness spring and the stiffness of the oil film is established.The three-dimensional model of the bearing system was made using Solid Works to account for the actual bearing size,and the fluid simulation study was completed using the fluid simulation program CFX to acquire the overall bearing temperature field,oil film pressure field,and air flow field.The initial condition for the Static Structural module’s thermodynamic coupling study was the temperature field in the solid domain as determined by conjugate heat transfer,and the workbench and oil pad were connected by a variable stiffness spring.It was possible to acquire the deformation fields of the oil film and other solid domains.After structural deformation,the bearing mesh was removed,and the fluid-structure coupling analysis was once more performed.Multiple iterations of the bearing morphology alteration process were run until the change in monitoring data was determined to have reached the simulation convergence criterion.When the temperature,pressure,and air flow fields of the oil film at the bearing’s final stable operation,as well as the deformed oil film and solid domain structure,were collected,the analysis was deemed complete.In order to simulate the dynamic change process of the bearing during operation,obtain the deformation results of the oil film and the solid domain at each stage,as well as the lubrication characteristics of the oil film at the corresponding stage,and summarize the rule,the unidirectional fluid-structure coupling method is used in this paper.It has been discovered that as rotating speed increases,so does the temperature of the oil film.While the maximum pressure keeps rising,the average oil film pressure first rises and then falls.The radial bearing oil film exhibits a thin inner and thick outside wedge following deformation,and the bearing as a whole exhibits a radial outward and oblique upward deformation trend.It can give a theoretical foundation for bettering the design and stability of a hydrostatic thrust bearing by summarizing the regulations.