A scheme based on the approximate solution determined by the method of multiple scales is proposed for the identification of nonlinear material parameters of a piezoelectric disc. The theoretical approach is experimentally validated to determine these parameters through dynamic electrical actuation. The identified material parameters are then used to investigate the nonlinear electro-elastic behavior of the disk, used as a receiver, in an ultrasound acoustic energy transfer system.
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Modeling and identification of electro-elastic nonlinearities in ultrasonic power transfer systems
We establish a nonlinear nonconservative mathematical framework for the acoustic-electro-elastic dynamics of the response of a piezoelectric disk to high-level acoustic excitation in the context of ultrasound acoustic energy transfer. Nonlinear parameter identification is performed to estimate the parameters representing nonlinear piezoelectric coefficients. The identification is based on exploiting the vibrational response of the disk operating in the thickness mode under dynamic actuation. The nonlinearly coupled electro-elastic governing equations, for the piezoelectric receiver subjected to acoustic excitation, are derived using the generalized Hamilton's principle. The method of multiple scales is used to obtain an approximate solution that forms the basis for parameter identification. The identified coefficients are then experimentally validated. The effects of varying these coefficients on the nonlinear response, optimal resistive electrical loading, and power generation characteristics of the receiver are investigated.
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- Award ID(s):
- 1711139
- PAR ID:
- 10105372
- Date Published:
- Journal Name:
- Nonlinear Dynamics
- ISSN:
- 0924-090X
- Format(s):
- Medium: X
- Sponsoring Org:
- National Science Foundation
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