Study On Fault Excitation And Transfer Characteristics Of Rolling Bearing Of Gas Turbine

Gas turbine is the core power device in the field of large surface ships and clean power generation.It has extremely high requirements for reliability and safety.Once a failure occurs,it is easy to cause serious accidents and even cause major losses.Among them,the power turbine rotor is its main core power rotating component,and the rolling bearing supporting the power turbine rotor is a component with a high incidence of failure.Combined with the structural characteristics and operating conditions of the ship's gas turbine bearings,a typical fault excitation force model of the bearing is established,the dynamic modeling of the gas turbine power turbine rotor-bearing system is carried out,and the fault vibration characteristics and diagnosis research of the power turbine-bearing support system are carried out.This article mainly focuses on modeling and analysis of rolling bearing faults.First,a simple rotor-bearing support system dynamics model is established based on the finite element method,and the rolling bearing model studied in this paper is analyzed for kinematics and failure frequency calculation.Modeling the typical faults of rolling bearings(outer ring failure,inner ring failure and roller failure),and analyzed the vibration signals under health status,outer ring failure,inner ring failure and roller failure,and carried out the above vibration signals Time domain waveform and frequency domain analysis verified the accuracy of the rolling bearing fault excitation force model.It laid the foundation for the follow-up research on the unbalanced response of the rolling bearing faults of the complete gas turbine.Taking the ship's gas turbine power turbine as a reference,the dynamic turbine rotor dynamic model is established by the finite element method based on the principle of dynamic similarity,and the critical speed and modal vibration of the dynamic turbine rotor under rigid support and elastic support are solved by the eigenvalue method Analysis of the influence of the unbalanced excitation force on the vibration response of the power turbine rotor and the effect of the position of the unbalanced excitation force on the vibration characteristics of the power turbine rotor.The dynamic model of the ship's gas turbine machine(casing-bearing-rotor)is established,and the research on the impact of the unbalanced excitation force on the vibration characteristics of the rolling bearing of the whole machine under single fault and the vibration characteristics of the whole machine under the coupling fault of rolling bearing are carried out.