Predictive modeling of ultrasonics SHM with PWAS transducers

This paper presents a set of analytical and numerical results on the use of guided waves for structural health monitoring application. The aim of the work presented in this paper is to provide tools to extend modeling capacities and improve quality and reliability of guided wave propagation models using commercially available finite element (FE) packages. Predictive simulation of ultrasonic non-destructive evaluation (NDE) and structural health monitoring (SHM) in realistic structures is challenging. The principle of guided wave propagation is studied and an analytical model is developed to obtain the analytical waveform and theoretical frequency contents solution of arbitrary engineering situations. Two benchmark problems, one 1-D and the other 2-D to achieve reliable and trustworthy predictive simulation of ultrasonic guided wave SHM with FEM codes have been proposed. The proposed 1-D benchmark problem will be a simple pitch-catch arrangement between a transmitter PWAS and receiver PWAS in a plate. The proposed 2-D benchmark problem will be the pitch-catch arrangement in a full 2-D plate involving circular-crested guided waves between a transmitter PWAS and receiver PWAS. In addition, a circular through hole of defined size ratio could be added to the 2-D problem to simulate the detection of damage, and assess the detectability threshold since closed-form solution exists for this problem too. The paper finishes with summary, conclusion, and suggestions for further work.