Nonlinear Poro-Visco-Thermal Vibrations in Piezo-Thermoelastic Hygroscopic Sandwich Shells

This study utilizes a multiple scales perturbation approach to analyze the nonlinear wave propagation characteristics of a doubly curved sandwich composite piezoelectric shell with a flexible core under hygrothermal conditions. Stress and strain computations for the flexible core and face sheets are conducted employing Reddy’s third-order shear deformation theory (TSDT) and third-order polynomial theory, respectively. The investigation delves into the combined effects of a multilayered shell, flexible core, and magneto-rheological layer (MR) in elucidating the nonlinear behavior of both in-plane and vertical moments within the core. The Halpin-Tsai model is employed to derive the properties of polymer/Carbon nanotube/fiber (PCF) and polymer/Graphene platelet/fiber (PGF) three-phase composite shells. The governing equations for the multiscale shell system are derived using Hamilton’s formulation. The study explores temperature fluctuations, diverse distribution patterns, curvature ratios, and electric fields through numerical analysis, with graphical presentation of results. Previous research has validated the accuracy of these methodologies. Notably, these factors significantly impact the frequency-amplitude curves of the smart structure.