Dynamic Modeling And Vibration Analysis Of Bearing Rotor System Based On Energy Method

As the most common power source or electrical appliance,rotating machinery is widely used in today's society.As an important component of rotating machinery,bearing-rotor system plays an important role during the healthy service of rotating machinery.However rolling bearing plays a supporting role in the bearing-rotor system.However,due to various factors such as errors in the installation or manufacturing process and poor use environment,rolling bearing has many kinds of faults.The most common fault is that caused by the local defects of rolling bearing.Therefore,it is necessary to establish a dynamic model of the bearing-rotor system and analyze its motion mechanism in the operation process of the rotating machinery,to diagnose and analyze the faults of the rotating machinery.The main contents are as follows:(1)Based on the energy method and Lagrange equation,the dynamic model of the bearing-rotor system is established.Considering the actual distribution of rotor mass,a new multi-disc rotor mass distribution method is introduced to model the rotor.The bearing defect model is constructed,and the failure mechanism of the bearing is described and studied.At the same time,considering the installation position of acceleration sensor in the actual experiment,the housing is modeled in the modeling process.(2)The influence of rotor mass distribution on the vibration response of bearing rotor system is discussed.By comparing the rotor mass with the experimental data,the validity of the model is verified firstly,and then the influence of the number and position of the rotor on the vibration response of the system is analyzed.(3)The influence of bearing local defect size and spindle speed on the vibration response of the system is compared and analyzed.The simulation signals of different defect sizes at the same speed were compared,and the influence of local defect sizes on the vibration response of the system was analyzed.At the same time,the simulation signals of different spindle speed under the same defect size are compared,and the influence of spindle speed on the vibration response of the system is analyzed.The results show that the vibration of the defective bearing in the bearing rotor system will be increased with the increase of the local defect size and the spindle speed.(4)The vibration signal of healthy bearing at fan end is analyzed.Through the modeling of the bearing in the fan end,the simulated vibration signal of the bearing in the fan end is obtained.The results show that the vibration signal at the fan end will produce the same frequency fault signal as the fault end and generate harmonics.At the same time,the multi-disc rotor mass distribution method also affects the vibration signal amplitude of the healthy bearing at the fan end.