Defect characterization potential via guided waves

A goal of this study is to advance the data of ultrasonic guided wave inspections applied to cylindrical tubing for defect detection, potential classification and sizing analysis. The purpose of this study is therefore to introduce procedures that might be capable of characterizing a defect located in a waveguide. Some results of a theoretical study on guided wave propagation in traction free and fluid loaded structures will be presented in order to demonstrate the nature of guided waves. A comprehensive review concerning a study on various guided wave propagation and bulk and guided wave scattering problems is presented. Finally, the use of the boundary element method for guided wave scattering problems is proposed with emphasis on its efficiency and accuracy for defect characterization. Reflection factors corresponding to multi guided wave modes generated via mode conversion on arbitrarily shaped defect surfaces can be calculated as a function of defect size, orientation, geometry of a wave guide and applied frequency by the boundary element method. This approach can be used to estimate the amount of ultrasonic energy being carried by multi mode signals reflected from a defect.