Identification Method Based On CFD Of Dynamic Characteristic Coefficient Of Sliding Bearing

As rotary machinery with large scale,high speed and large capacity is developed,the vibration fault in rotor-bearing system appears more and more.So journal bearing becomes the focus of keeping good dynamic quality in rotary machinery.In the study of dynamic of rotor-bearing system,the research of sliding bearing oil film parameters is essential.This paper presents a sliding bearing dynamic coefficients of different frequency eddy recognition method based on complex function relation is established between the shaft static equilibrium position disturbance and oil film force,x and y to the same amplitude but based on the different frequency perturbation method,using FFT to obtain oil film force spectrum characteristics,this method only through a perturbation calculation can identify 8 dynamic coefficients.Firstly,the applicability and accuracy of the recognition method are verified through an example of short round tile which is determined the accuracy of the identification method.Then,based on the two-phase flow model,the three-dimensional calculation model of the sliding bearing is established.The static characteristics of the bearing are calculated by CFD technology,and the grid independence of the modified model is divided into four different grids.Meanwhile,the finite difference method,the Dyrobes and the short bearing model are used to calculate the same parameter of the sliding bearing.Compared with the CFD calculation results,the accuracy and validity of the CFD calculation result is verified.Finally,considering the cavitation effect and static equilibrium position,solving the dynamic grid technology x and y direction of different frequency perturbation under the oil film force frequency variation by harmonic excitation principle and CFD,continue to use disposable identified 8 dynamic characteristic coefficients identification method for dynamic characteristic.Then,the disturbance condition is changed and the influence of the disturbance frequency and the amplitude of the disturbance on the dynamic characteristic coefficient is analyzed.