Non-intrusive stress measurement system

rdf:langString Non-intrusive stress measurement system

rdf:langString Non-intrusive stress measurement (system), or NSMS, is a method for determining dynamic blade stresses in rotating turbomachinery. NSMS is also known by the names "blade tip timing" (BTT), "arrival time analysis" (ATA), "blade vibration monitoring" (BVM), Beruehrungslose Schaufel Schwingungsmessung (BSSM), and "blade health monitoring" (BHM). NSMS uses externally mounted sensors to determine the passing times of turbomachinery blades. The passing times after conversion to deflections, can be used to measure each blade's vibratory response characteristics such as amplitude/stress, phase, frequency and damping. Since every blade is measured, stage effects such as flutter, blade mistuning, and nodal diameter can also be characterized.The measurement method has been used successfully in all stages of the gas turbine engine (fan, compressor, and turbine) and on other turbo-machinery equipment ranging from turbochargers to rocket pumps. The ability to apply the technology to a given situation is dependent upon a sensor type that can meet the environmental requirements.