Fault Characteristics And Location Quantitative Identification Of Cracked Hollow Shaft Rotor Of Heavy Duty Gas Turbine

Rotating machinery plays an important role in the process of industrial development in China.Crack failure is a common fault form during the service of rotor system.The occurrence of cracks will cause very serious production accidents and property losses.In this paper,the characteristics of breathing crack and normal open crack are studied respectively for heavy gas turbine,and the characteristic frequency and equipment fault diagnosis system are established to prevent large accidents.Based on the structure characteristics of heavy gas turbine,the model is established,and the cosine model is used to model the crack element.The matrix of the assembly dynamic equation is established by the finite element method of rotor dynamics and Timoshenko beam theory needle.Finally,the dynamic equation of cracked rotor is obtained.In this paper,we use the more mature Newmark method to solve the dynamic equation,and find that there is resonance peak at subcritical speed.The crack characteristics of heavy gas turbine rotor are analyzed with several subcritical speeds as the starting point.In view of the breathing crack,the crack fault characteristics are investigated by the location of the crack,the crack depth,and the angle between the unbalance and the crack in practical application.The spectrum diagram,time waveform and axis track chart are obtained by time-frequency transformation,and the characteristics are analyzed and the rules are summarized,Finally,the characteristic frequency of respiratory crack model is the x component at subcritical speed.According to the normal crack model,the investigation index is unchanged,the investigation index is unchanged,the vibration characteristics of the rotor system with the normal crack are analyzed and the rules are summarized.Finally,it is found that the 2X component at the subcritical speed is the characteristic frequency of the normally open crack model.According to the idea of agent model,Kriging agent model is constructed by taking crack location and crack depth as input,and vibration response of each point as output.The performance of different agent models is evaluated and optimized by mean square error MSE and RMSE,Finally,the crack diagnosis of heavy gas turbine is realized with high precision through computer test.