Bladed Disk Crack Detection Through Advanced Analysis of Blade Passage Signals

Crack initiation and propagation in the bladed disks of aero-engines caused by high-cycle fatigue under cyclic loads could result in the breakdown of the engines if not detected at an early stage. Although a number of fault detection methods have been reported in the literature, it still remains ver...

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Bibliographic Details
Main Author: Alavifoumani, Elhamosadat
Other Authors: Liang, Ming
Language:en
Published: Université d'Ottawa / University of Ottawa 2013
Subjects:
Online Access:http://hdl.handle.net/10393/24170
http://dx.doi.org/10.20381/ruor-3011
Description
Summary:Crack initiation and propagation in the bladed disks of aero-engines caused by high-cycle fatigue under cyclic loads could result in the breakdown of the engines if not detected at an early stage. Although a number of fault detection methods have been reported in the literature, it still remains very challenging to develop a reliable online technique to accurately diagnose defects in bladed disks. One of the main challenges is to characterize signals contaminated by noises. These noises caused by very dynamic engine operation environment. This work presents a new technique for engine bladed disk crack detection, which utilizes advanced analysis of clearance and time-of-arrival signals acquired from blade tip sensors. This technique involves two stages of signal processing: 1) signal pre-processing for noise elimination from predetermined causes; and 2) signal post-processing for characterizing crack initiation and location. Experimental results from the spin rig test were used to validate technique predictions.