Dynamic Analysis And Simulation Of Rolling Bearing-Rotor System

The rolling bearing-rotor system is being used widely in rolling machines today,the dynamic characteristic of this system has attracted more and more attention becauseof its effect on the holistic performance of machine. The thrust-weight ratio of thesystem is increased mainly by raising the DN values of the bearings used in the system.A high DN value will certainly increase the generation of heat by the inner frictionbetween the bearing elements, so the condition of the generation of heat by friction isalso paid great attention by people.In this paper, combining the rolling bearing dynamics, the rotor dynamics and themulti-body dynamics, a mathematical model and the multi-body dynamic differentialequations of the interaction between bearing elements were developed. Besides, themathematical model about the friction power consumption of bearings was establishedbased on the tribology, ADMAS was used as the research platform, the user subroutinewas written with Fortran language, and the dynamic model was bridge-connected withthe friction power consumption model using the complier-generated dll document,which realized studying the generation of heat by friction based on dynamics.Taking the bearing-rotor system of a special cage test rig for example, both theeffects on the system power loss and the dynamic characteristic of the bearing cage thatthe working condition and the internal structure parameters of the system had wereanalyzed through the simulation calculation, the rationality and the reliability of thedynamic model and the friction power loss model established were proved by test. Theresults show that,1the gross friction power loss of the system increases with theincreasing working speed.2The gross friction power loss increases with the radial load,but the different bearing in the system shows different trend of variation.3the grossfriction power loss increases with the axial load.4the gross friction power loss willdecrease with the increasing coefficient of raceway groove curvature radius.5theincreasing of cage pocket clearance and the guided clearance, to some extent, will decrease the gross friction power loss.6if the diamentral clearance of the cylindricalroller bearing raises, the gross friction power loss of the system will also increase.7theskidding of cage occurs more frequently with the increasing working speed, increasingthe radial working load can decrease the skid rate, and with the axial working loadraising, the skid rate will decrease slightly, when the radial working clearance increases,the skid rate of cage increases. the smaller clearance of pocket can decrease the skidratio effectively, the guided clearance shouldn’t be too small, because when theclearance is smaller, the skid ratio will be lager.