Research On Dynamic Balancing Method Of High Speed Rotor Bearing System Without Trial Weight Based On Dynamic Model

High-speed rotors are widely used in modern industrial production.In the cutting process,the rotating state of the rotor is the main reason that affects the accuracy of the cutting parts.The essential cause of rotor vibration is that its mass center and geometric center line do not coincide.The vibration of the rotor will bring processing errors,affect production efficiency,and even cause industrial accidents in serious cases.Therefore,it is of great significance to study the unbalanced vibration suppression method of high-speed rotor system.In this paper,the finite element dynamic model of the high-speed rotor-journal bearing system is established.Based on this model,a multi-speed dynamic balancing method without trial weight is proposed.The main research contents are as follows:Firstly,the structure and force of sliding bearings are analyzed,and the stiffness and damping matrix of sliding bearings are calculated.The beam element model and the disc element model of the spindle are established by using the finite element method.The bearing,beam element and disc element modules are integrated to obtain the finite element dynamic model of the high-speed rotor-bearing system.The finite element model of the system is simulated by using MATLAB to calculate the natural frequency and mode shape of the rotor.Compared with the simulation results of ANSYS model and Dy Ro Be S software,the similarity of the results of the three models is higher.Combining with the actual measurement of the experimental platform,it is proved that the established rotor model is accurate and reliable.Secondly,on the basis of accurately establishing the finite element model of the system,a model-based multi-speed non-trial gravity dynamic balance method is proposed,and the theoretical derivation is carried out.The simulation results show that the method can accurately identify the unbalance of the rotor(including quality information and phase information).Considering the influence of the disturbance that may occur in the experimental test on the solution results,the ill-conditioned problem in unbalanced solution is studied.Finally,modal experiments and dynamic balancing experiments are carried out on the rotor test bench.The basic information of the rotor is obtained through modal experiments and compared with the model.The unbalanced vibration of the rotor is obviously reduced by adding the identified unbalance in the dynamic balancing experiment,which proves that the unbalanced suppression method is effective and feasible.Through the work of this paper,a feasible and effective method of dynamic balancing without trial weight is obtained,which provides a new way for the application of dynamic balancing technology in engineering practice and has important research significance.