Study On Typical Vibration Fault Mechanism Modeling And Response Characteristics Of Certain Aero Engine Rotor System

Aero-engine is the power plant of the aircraft. With the rapid development of modern aviation technology, the engine structure of aviation has become more complex. Given a lot of fault type on engine rotor vibration characteristics have obvious reaction, at the same time, the vibration data which we can get from the aircraft engine is so important, so this paper mainly studies the engine rotor vibration response in the event of a typical fault. Then we can extract the fault feature distinguish between fault types and fault parts and positioning them.This paper mainly against the rotor system architecture of aircraft engine concentrated quality standard, respectively set up five models by Newton's laws of motion and rotor dynamics. They are a single mechanical model, single disk rotor system model, double disk single rotor system model, the double rotor without intermediate bearing model and casing coupling vibration model. Secondly we establish differential equations of system movement respectively and solve them with the fourth order Runge-Kutta based on Matlab. Then we draw and analyze its corresponding response graphics axis path(including axis path diagram, time domain waveform figure, spectrum, Poincare, bifurcation diagram and frequency spectrum waterfall figure).Through the study of rotor imbalance model, found the characteristic response of rotor vibration when the unbalanced fault occurs. Through the study of rotor bearing misalignment model, found the characteristic response of rotor vibration when the bearing misalignment fault occurs. Through the study of single-disc single rotor model, found the characteristic response of rotor vibration when the single-disc single rotor happen the rubbing fault. Through the study of Double-disc single rotor model, found the characteristic response of rotor vibration when the rubbing faults happen in different parts of rotor. Through the study of vibration coupling model that between the double rotor system and casing, explored the way to distinguish the type of system failure and locate the fault by the characteristic response of the rotor and the casing vibration. Provide theoretical support for further research aircraft engine condition monitoring, the diagnosis of fault and the location system of fault in the future.