Experimental Investigation On Vibration Characteristics Of Aero-Engine Rotor Fault

The aero-engine is a rotational machine with high speed, its reliability not only affects the flight safety of airplane directly but also ensures the working safety of aero-engine in rig test. The fault diagnosis and state monitoring of aero-engine become more and more important research hotspot in aero-engine industry.It is a very important basis to do the condition monitoring and fault diagnosis of the aero-engine that measure the vibration of whole aero-engine and identify the vibration characteristics of aero-engine faults accordingly. In this paper we describes how to extract some typical vibration features of the aero-engine faults phenomena such as rotor filled with liquids, rotor rubbing and rolling element bearing in details through the experimental study and the fault phenomena representation of aero-engine and by the use of vibration measurement and frequency spectrum analysis as well as theoretical analysis. We got the variation rule of the rotor system by changing the fluid viscosity and fluid volume and analyzing the rotor vibration signal in the fault analysis of rotor filled with liquid. In the experimental investigation of the rotor rubbing fault, the relation between the rubbing force and the vibration stress under the single point and two point rubbing as well as partial rubbing occurred at critical rotational speed and the relation between the rubbing area and vibration stress are analyzed for the two conditions that the support stiffness of the rotor system is strongest or weakest. The faults causes of the rolling element bearing are also extracted by analyzing the vibration signal and comparing with the disassembly bearings after trial and test in the experimental study of the fault of rolling element bearing.Experimental results are verified by analyzing the dynamic characteristics of rotor models and the relevant vibration signal for some type aero-engine. The very important foundation is established for creating the database of the faults diagnosis of aero-engine and a scientific basis is also provided for the condition monitoring and fault diagnosis of aero-engine during its rig test in the future.