Study On Thermo-mechanical Coupling And Vibration Of Tapered Roller Bearings In Wind Power Gearbox

Rolling bearings are the core components of mechanical equipment.They have the advantages of strong load-bearing capacity,low friction loss,and high precision.Therefore,they are widely used in the engineering field.Bearing failure at the output end of a wind power gearbox is an important cause of wind power gearbox failure.The factors that cause bearing failure are complex,and the working condition of the bearing has a direct impact on the service life and service performance of the equipment,so the cause of bearing failure is studied Is of great significance.This thesis mainly studies and analyzes the output shaft tapered roller bearing thermal-mechanical coupling problem and the shafting radial coupling vibration problem.The thermal analysis model and the shafting coupling vibration model of the tapered roller bearing are established respectively,and the bearing is analyzed through simulation calculations.Various characteristics have been studied.Since there is always a slight position error in the center of the inner and outer rings during the installation of the bearing,this will introduce additional displacement and increase the radial load on the bearing.In order to study the stress field and temperature field characteristics of the bearing with assembly position deviation,this paper established an analysis model of the tapered roller bearing with the radial position deviation of the inner ring and the fixed outer ring in the finite element analysis software.The model considers the temperature and The interaction mechanism between stresses is suitable for the complete thermo-mechanical coupling analysis of bearings.In order to explore the relationship between the bearing contact stress,temperature characteristics and the degree of deviation of the assembly position,multiple sets of simulation calculations were designed and carried out,the data sets were processed and compared,and a regular summary was made.According to the output results obtained,the contact load,deformation and offset caused by the position deviation are in a linear relationship,but the increase in the assembly position deviation will increase the contact area area,the number of bearing rollers,and the contact force will increase approximately exponentially.In addition,the temperature history of the load-bearing area and the non-load-bearing area also show different changes.The vibration of the high-speed shaft bearing of the wind power gearbox is an important factor causing the safety hazards of the wind turbine,and the coupling effect of the shaft system will have an important impact on the bearing vibration.Taking the wind turbine gearbox high-speed shaft multi-support shaft system as the research object,based on the central difference method,a modeling method for analyzing the coupling vibration of the multi-support shaft system is proposed.The shaft coupling vibration equation is established.After the equation is decoupled,The equation is solved by the central difference method,and the oil film stiffness and viscous damping are considered when calculating the interaction force of each part of the bearing.Finally,the radial vibration history of the supporting bearing is calculated with the help of computer programming.The results show that the vibration amplitude of the coupled model is smaller than that of the uncoupled model;the contact force of different bearings on the shaft is different,and the closer the load application point is to the bearing,the greater the contact force;when the load application point is on the side close to the single bearing,it will There is a situation where the contact force is much greater than the double bearing on the other side.