Abstract:

This study examines the wave propagation behavior of functionally graded (FG) piezoelectric sandwich doubly-curved nanoplates subjected to thermo-electric loading. The sandwich nanoplates are composed of a piezoelectric layer and an FG interlayer, deposited on a viscoelastic substrate, where the material parameters of the FG interlayer are influenced by temperature variations. By establishing a nonlocal strain gradient constitutive equation that incorporates piezoelectric and thermal effects, the displacement and strain fields of doubly-curved structures are formulated within the framework of first-order shear deformation theory (FSDT). The governing equations are derived using Hamilton’s principle, and then the dispersion relations for the doubly-curved nanoplates are computed through harmonic solution methods. Finally, the systematic analysis is conducted to investigate the effects of curvature parameters, scale parameters, FG indices, and foundation parameters on the wave propagation characteristics. The findings contribute to a deeper understanding of the wave propagation behavior of complex doubly-curved sandwich structures.

Key words: piezoelectric sandwich structure, nonlocal strain gradient theory (NSGT), viscoelastic foundation, doubly-curved plate, wave propagation