A helical-based ultrasonic imaging algorithm for structural health monitoring of cylindrical structures

Condition assessment of pipeline networks is critical to ensure operation safety considering that the network around the US is aging. This work aims at combining guided ultrasonic waves and advanced tomographic algorithms to locate corrosion-induced defects in both inner and outer surfaces of steel pipes. Particularly, it employs guided ultrasonic waves that propagate on helical paths around pipes. The novelty of this work is in using high orders of the so-called helical guided ultrasonic waves (HGUW), which can significantly increase the inspection area with a minimum number of sensors. Algebraic reconstruction technique (ART) is then implemented in order to gather information from the wave propagation through the pipe and asses possible locations where defects might exist. To validate the proposed imaging algorithm, numerical simulation and experiments were carried out. The final results suggest that the proposed imaging algorithm can be effectively used for continuous monitoring of corrosion damage in pipelines.