Modeling And Dynamic Analysis Of Rolling Bearings Considering Dynamic Friction

Rolling bearings are widely used in various fields in rotating machinery,its role is mainly to reduce wear and ensure the smooth operation of equipment,its performance is one of the important factors affecting the dynamic characteristics of rotating machinery.When bearing failure occurs in rotating machinery,it will affect the stable operation of the equipment,and in serious cases may lead to equipment damage,as well as the threat to the safety of the operator.In high-speed rolling bearings,the frequent collision between cage and roller will affect the dynamic performance of the bearing,therefore,it is crucial to study the dynamic characteristics of rolling bearings in rotating machinery,and there is still less research on the collision between cage and ball in rolling bearings.This paper takes the collision of cage and rolling body as the engineering background,considers the motion of the roller position and the bearing radial load angle of 0 point,considers the collision between the roller and cage and the force between the parts,and establishes a class of cylindrical roller bearing with clearance frictional collision vibration system model.Based on the proposed kinetic analysis theory of bearings for cylindrical roller bearings,the collision between cage and rolling element is regarded as discontinuous,and the differential equations of system motion are listed according to its mechanical model and actual motion.At the same time,the fourth-order Runge-Kutta method with fixed step length is used to introduce the Dankowicz kinetic friction and improved Lugre kinetic friction models respectively,and the kinetic equations of the system are listed according to Lagrange’s theorem and momentum conservation theorem,and the viscous slip chattering phenomenon of the system is discussed after its dimensionless processing.Based on the above theoretical analysis model of the system,this paper further considers the introduction of Dankowicz kinetic friction and improved Lugre kinetic friction model,and obtains the bifurcation diagram,Poincaré cross section,phase diagram and time course diagram of the system when the excitation frequency,clearance and stiffness coefficient are varied by selecting specific parameters and using C language programming simulation,and analyzes the system under the influence of different structural parameters The dynamic behavior of the system under the influence of different structural parameters was analyzed.When Dankowicz kinetic friction is introduced,it is shown that: with the change of excitation frequency,the system mainly shows the mutual transition between period and chaos,and several inverse period multiplication bifurcations,as well as Bare-grazing bifurcations from period to chaos directly;the system mainly shows the chattering,rubbing collision and inverse period multiplication bifurcations with the change of collision gap,and it should be avoided as much as possible.The gap is too small or too large.When the stiffness coefficient is changed,the system period motion interval is larger and there are sudden changes,so a larger stiffness coefficient should be chosen.When the improved Lugre friction is introduced,the study shows that: when the excitation frequency changes,the system has multiple Hopf bifurcations and enters chaos through phase locking,accompanied by a small amount of sticky phenomenon;when the system changes with the gap,there are sticky and Hopf bifurcations,so the gap should be avoided too small;the system has a large chaotic window when the stiffness coefficient is small,accompanied by a small amount of sticky phenomenon,in engineering In practice,a larger stiffness factor should be selected.