Finite-Element Analysis of Lamb Wave Propagation in a Thin Aluminum Plate

Structural health monitoring (SHM) is an emerging technology that can be used to identify, locate, and quantify structural damages before failure. Among SHM techniques, Lamb waves are widely used since they can cover large areas from a single location. The development of various structural simulation programs has lead to increasing interest in whether SHM data obtained from the simulation can be verified by experimentation. The objective of this research is to determine the Lamb wave responses of SHM models using the finite-element software package ABAQUS CAE as a computational tool for an isotropic plate. These results are compared to experimental results and theoretical predictions under isothermal and thermal gradient conditions to assess the sensitivity of piezoelectric generated Lamb wave propagation. Simulations of isothermal tests are conducted over a temperature range of 0–190°F using 100 and 300kHz as excitation frequencies. The changes in temperature-dependent material properties are used to measure the differences in the response signal’s waveform and propagation speed. An analysis of the simulated signal response data demonstrated that elevated temperatures delay the Lamb wave propagation, although the delays are found to be minimal at the temperatures tested.