Advanced, Ultra-High Frequency Vibration Monitoring for Improved Turbine Engine Diagnostics and Prognostics

Impact Technologies, in collaboration with Epoch Engineering, Pratt & Whitney, and Rolls Royce/Allison, is currently developing a unique health management system that integrates high fidelity, vibration and acoustic emissions data with advanced featureextraction and fault isolation algorithms to effectively assess turbine engine rotordynamic and mechanical system faults. The prototype system that will be delivered and demonstrated in the USAF's T-63 Test Cell will provide early detection and severityassessment of alignment/imbalance problems as well as gear/bearing/shaft/disk faults by utilizing multiple regions of the vibro-acoustic energy spectrum (DC to 100's of kHz). The multiple bandwidth strategies and specific algorithms being implemented inPhase I and planned for Phase II are based on the team's comprehensive knowledge of how military engines are operated and maintained, as well as how faults develop and propagate over the life of an engine. Advanced diagnostic features derived from acousticemission waveform analysis, high-frequency enveloping/demodulation, wavelets, and more traditional time/frequency domain processing are being combined with automated classification techniques to develop this information-rich, health monitoring system. Thesystem will use data collected from test cells during engine pass-off, on-airframe installations, and potentially in-flight investigations to evolve a comprehensive database for robust fault identification and damage tracking. Using this broadbandmonitoring capability, along with relevant health monitoring features, models, maintenance database information, and various automated prediction technologies, a state-of-the-art system that identifies engine faults more confidently and at an earlier stagecan be developed for commercial and Air Force applications.