Stress wave analysis of turbine engine faults

Stress Wave Analysis (SWAN) provides real-time measurement of friction and mechanical shock in operating machinery. This high frequency acoustic sensing technology filters out background levels of vibration and audible noise, and provides a graphic representation of machine health. By measuring shock and friction events, the SWAN technique is able to detect wear and damage at the earliest stages and is able to track the progression of a defect throughout the failure process. This is possible because as the damage progresses, the energy content of friction and shock events increases. This 'stress wave energy' is then measured and tracked against normal machine operating conditions. This paper describes testing that was conducted on several types of aircraft and industrial gas turbine engines to demonstrate SWAN's ability to accurately detect a broad range of discrepant conditions and characterize the severity of damage.