Localizing Common Faults for Improved Aero Engine Maintenance

Abstract

As industry moves towards implementing next generation Integrated Vehicle Health Management (IVHM) systems, the ability to quickly localize common faults in aero engines for improved maintenance is an important step in realizing this aim. Using a combination of high-fidelity finite element simulations and system level models, common unbalance faults have been studied for the purposes of localization. Looking at stationary and rotating vibration phenomena, features for fault localization have been identified and discussed from the perspective of implementation in future IVHM systems for rotating machinery. This includes studies into both the lower and the higher end of the frequency spectrum, looking at mode shapes, frequency response functions and forces at the bearing points in static conditions. Under rotating conditions, Campbell diagrams and transient analysis have been considered. In order to evaluate using the features identified, system level models have been created using Craig-Bampton reduction techniques, which are capable of recreating the studies conducted using the higher-fidelity finite element models. A discussion on introducing model based reasoning techniques to the system level model in order to adapt it for future IVHM systems are discussed. In turn, this leads to a discussion on a methodology for localizing faults in a wide range of rotating machines.