Ultrasonic Guided Wave for Long Range Monitoring and Nondestructive Evaluation (NDE) of Corrosion Induced Defects in Shipboard Piping with Complex Geo

Although various technologies exist for piping NDI, the complexities that exist in Navy piping systems make the task of inspecting these structures more difficult than their civilian counterparts. Navy vessels consist of pipes of various sizes that transport fuel, water, and sanitation, and are often within cramped spaces, pass through bulkheads, and filled tanks that are inaccessible to inspectors. They also often have elbows, bends, twists and branches, but current inspection technology has only been truly successful on straight featureless pipes. We have demonstrated previously the ability to extract information about multiple modes from guided wave signals using the dynamic wavelet fingerprinting (DWFP) technique. We propose here a different inspection technique that uses normal incidence transducers to generate feature-rich multi-mode signals as opposed to single axisymmetric or flexural modes. A large portion of this work will be focused on numerically and analytically exploring the complicated scattering and propagation of the guided waves past bends, different types of corrosive flaws, and other structural complexities. Then, with the DWFP multi-mode detection technique and knowledge gained from the numerical and analytical studies, individual modes can be monitored and any changes can be used to detect and localize flaws in complex piping systems.