Mechanical Engineering Commons^™

Structural Health Monitoring Using Ultrasonic Guided Waves And Piezoelectric Wafer Active Sensors, Faisal Haider Mohammad

Theses and Dissertations

This dissertation is organized in three major parts covering ardent and challenging research topics in structural health monitoring (SHM). Part I focuses on the theoretical and numerical analysis of acoustic emission (AE) guided waves in both Cartesian coordinates (2D) and cylindrical coordinates (3D) system using energy approach, which, to the best of our knowledge, has not been yet reported elsewhere. AE guided waves appear due to sudden energy release during incremental crack propagation in a plate. The Helmholtz decomposition approach is applied to the inhomogeneous elastodynamic Navier-Lame equation for both the displacement field and body forces. For the displacement field, …

Physics Based Modeling Of Guided Waves For Detection And Characterization Of Structural Damage In Nde And Shm, Banibrata Poddar

Theses and Dissertations

Guided waves based damage detection techniques are popular for their ease of generation and detection along with their ability to travel long distances. Accurate and efficient modeling is a key for successful implementation of guided waves for NDE/SHM. However, efficient prediction of scattering from various damage is challenging due to the complex nature of these guided waves.

This dissertation presents as physics based efficient and accurate modeling techniques to predict ultrasonic wave propagation and their interaction with various damage. Detection and characterization of damage in structures can typically be divided into two categories, active and passive. This research is aimed …