Software for In-Flight Detection of Widespread Fatigue in Engine Disks

The proposed project will demonstrate unique digital signal processing software for automated, early detection of Widespread Fatigue (WF) damage in turbine engine disks. The software, known as RVMD is based on recently patented technology in Rotational Vibrationa Monitoring (RVM). RVMD will measure loss of disk structural rigidity due to WF defects, both from High Cycle and Low Cycle Fatigue. Commercial applications include maintenance checks and in-flight monitoring. By detecting WF, RVMD will help prevent disk failures and improve safety for the flying public. Phase I will show RVMD detects reactive disk resonance modes in a model bladed disk by processing tachometer signals, without using traditional vibration sensors. It has two objectives; 1) identify 0D, 1D and 0C disk modes, 2) measure mode shifts due to simulated fatigue cracking. Two commercial engine manufacturers have committed to Phase II. To date, the original RVM algorithm has been applied successfully in detecting blade and shaft resonances in axial flow compressors, industrial prop fans, and electric power turbines. Currently, RVM is also being applied to HCF detection in engine fan blades with Air Force support.