Monitoring of mechanical changes in a pipe assembly with complex geometry using multi-mode acoustic signals

Guided wave ultrasonic testing has been widely used for nondestructive and long-range evaluation of diverse mechanical structures, such as pipes plates. In general, a large number guided modes exist even in the simplest geometries, they exhibit highly dispersive characteristics. Thus, sophisticated excitation methods elaborate modal analyses need to be implemented excite, acquire, process well-defined pure part measurement method. If interrogated structure complex geometry, example, with cross-sectional variations or multiple joints, utilization becomes significantly more difficult. To overcome this difficulty, paper proposes use multi-mode, multi-frequency waves inspection structures arbitrarily geometries. Using broadband chirp signals multi-mode time–frequency analysis prototypical pipe assembly that includes diameters, elbows, flange connections, we experimentally show sensitive detection changes (both material addition loss). addition, demonstrate complexity can modeled digital domain sufficient detail allow accurate numerical simulation acoustic response using