Fully coupled electromechanical elastodynamic model for guided wave propagation analysis

Abstract

Physics-based computational models play a key role in the study of wave propagation for structural health monitoring (SHM) and the development of improved damage detection methodologies. Due to the complex nature of guided waves, accurate and efficient computation tools are necessary to investigate the mechanisms responsible for dispersion, coupling, and interaction with damage. In this paper, a fully coupled electromechanical elastodynamic model for wave propagation in a heterogeneous, anisotropic material system is developed. The final framework provides the full three dimensional displacement and electrical potential fields for arbitrary plate and transducer geometries and excitation waveform and frequency. The model is validated theoretically and proven computationally efficient. Studies are performed with surface bonded piezoelectric sensors to gain insight into the physics of experimental techniques used for SHM. Collocated actuation of the fundamental Lamb wave modes is modeled over a range of frequencies to demonstrate mode tuning capabilities. The displacement of the sensing surface is compared to the piezoelectric sensor electric potential to investigate the relationship between plate displacement and sensor voltage output. Since many studies, including the ones investigated in this paper, are difficult to perform experimentally, the developed model provides a valuable tool for the improvement of SHM techniques.

Multiscale Modeling of Advanced Materials for Damage Prediction and Structural Health Monitoring

“…In this work, a fully coupled electromagneto-mechanical elastodynamic model for wave propagation in heterogeneous, anisotropic material systems is developed (Borkowski, Liu, and Chattopadhyay, 2013a; …”

“…The derivation for the fully coupled electromechanical LISA/SIM formulation (Borkowski, Liu, and Chattopadhyay, 2013a) is extended in this chapter to include magnetic coupling. The incorporation of piezomagnetic coupling into the theory further expands the capabilities of the LISA/SIM framework to simulate more complex actuation and sensing in GW and electromagnetic damage detection models as well as the dynamic behavior of electromagnetic coupled composites.…”

“…Although each of these numerical modeling techniques has merit, LISA/SIM is used in this study because of its proven accuracy in simulating ultrasonic elastic wave propagation, including GWs (Delsanto et al, 1992;Delsanto et al, 1994;Delsanto, Schechter, and Mignogna, 1997;Sundararaman, 2007), as well as its computational efficiency (Delsanto, Schechter, and Mignogna, 1997;Borkowski, Liu, and Chattopadhyay, 2013a).…”

“…However, many of the current GW propagation modeling approaches, including EFIT, require dissimilar material properties, often present in composite materials or specimens with damage, to be smeared or averaged across the cell interfaces. Therefore, due to the proven capability of the LISA/SIM numerical modeling scheme to accurately model wave propagation across sharp material boundaries such as damage (Delsanto, Schechter, and Mignogna, 1997;Sundararaman, 2007) as well as its proven computational efficiency (Delsanto, Schechter, and Mignogna, 1997;Borkowski, Liu, and Chattopadhyay, 2013a), this technique is well-suited for use in a virtual sensing framework for damage detection and quantification. However, the application and accuracy of the LISA/SIM technique has been limited because the actuation and sensing of wave signals using piezoelectric and piezomagnetic transducers has not been considered until recently (Borkowski, Liu, and Chattopadhyay, 2013a;.…”

“…In Borkowski, Liu, and Chattopadhyay (2013a) the authors incorporated electromechanical coupling within the LISA/SIM framework to allow piezoelectric actuation and sensing to be explicitly modeled. To further extend the theory, piezomagnetic coupling (i.e., magnetomechanical) was incorporated to provide the capability to model noncontact magnetic actuation and sensing as well as other electromagnetic NDE testing approaches .…”