Theoretical and experimental researches on nonlinear snap-through mechanism of bistable asymmetric composite laminated cantilever plate under foundation excitation in wind turbine blade skin

The exponential growth of the wind energy infrastructure has propelled a progressive increase in the wind turbine blade dimensions to optimize the energy harvesting capacity. Nevertheless, the conventional blade structures confront the critical challenge in the structural reliability and aerodynamic load. These multifaceted challenges have driven the need of the systematic investigation for the bistable composite laminates emerging as a strategically significant research direction to reconcile these competing engineering requirements. This paper investigates the nonlinear modeling and dynamic snap-through mechanism of the bistable asymmetric composite laminated (BACL) cantilever plate under the foundation excitation. A 4-degree-of-freedom nonlinear analytical model is introduced based on the classical plate theory, von Karman geometric nonlinearity, Hamilton principle and Rayleigh-Ritz method. The static stable initial values and first resonant frequency are derived for each configuration. Using the transverse foundation excitation as a triggering mechanism, the dynamic behaviors with varying frequencies and amplitudes are explored. The significant vibrations around two resonant frequencies corresponding to the stable configurations exhibit the approximate linear and distinctly nonlinear softening behaviors, respectively. The study identifies the critical frequency and amplitude ranges for the dynamic transformations and continuous snap-through phenomena. It is revealed that the snap-through characteristics, including the multiple harmonic resonances and chaotic dynamic behaviors, align closely with the experimental results. Focusing on the deformation behaviors, this study can support the development of the wind turbine blades.