Study On The Damping Characteristics Of Tilting Pad Sliding Bearing System

Compared with rolling bearing,sliding bearing has the advantages of stable operation,low noise and small vibration.In some occasions with high precision and higher vibration control requirements,the damping performance of sliding bearing can not meet the requirements.This paper mainly according to the damping characteristics of oil film of sliding bearing,researching the damping characteristics of tilting pad bearing with two layers of oil film against journal bearing.Specifically,the main research contents and achievements are as follows:1.Established equation of the Reynolds equation of tilting pad sliding bearing based on the hydrodynamic lubrication theory of sliding bearing.According to the instantaneous oil film thickness and disturbance pressure of tilting pad bearing,establish equation of perturbation pressure Reynolds equation of tilting pad bearing.To solve and analysis the tilting pad perturbation pressure by using COMSOL PDE toolbox,get the relationship between perturbation pressure,oil film stiffness,damping and perturbation frequency.2.The vibration models of the journal bearing-rotor system and the tilting pad bearing-rotor system have been established in the vertical direction,and the differential equations of motion were derived,and the vibration response characteristics of the rotor were analyzed.Rely on MATLAB/Simulink to establish simulation model of vibration response of journal bearing-rotor system and tilting pad bearing-rotor system.Analysis of rotor vibration of bearing-rotor system under different parameters.Research the damping characteristics of tilting pad bearing-rotor system against journal bearing-rotor system.The analysis results show that under the certain kinetic parameters,tilting pad bearing system has damping property.3.In order to reflect the dynamic characteristics of the tilting pad bearing system better,it is necessary to study the whole bearing-rotor-base system.The content of vibration problems of the bearing-rotor-base system can be described by system,excitation and response.Known excitation and response to request characteristic parameters is called modal analysis of vibration system.By using the modal analysis method to research vibration characteristics of bearing-rotor-base system,and to provide the basis for the comparison of vibration characteristics of journal bearing and tilting pad bearing analysis.4.Carry out the contrast tests of vibration characteristic of journal bearing and tilting pad bearing.Including the contrast of the rotor displacement amplitude and the average vibration acceleration level of footings between journal bearing and tilting pad bearings.Including the contrast of the average vibration acceleration level of footings of tilting pad bearing of different clearance ratio.Including the contrast of the vibration acceleration level of different measure point in low frequency band between journal bearing and tilting pad bearings.Test analysis results show that tilting pad bearing system has damping property under certain parameter conditions.