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Bistable composite laminates have the potential advantage in the fields of wind energy harvesting and deformable wings, which involve many fluid–structure interaction issues. This paper presents the fluid–structure interaction analysis of a cantilevered bistable hybrid symmetrical laminate (BHSL) in the uniform wind. In this work, a finite element model based on the Lattice Boltzmann Method (LBM) is used to analyze the wind-induced response of the BHSL and its variations with respect to wind speed and laminate length. Then, the wind-induced vibration behavior of BHSL is verified by wind tunnel tests. The finite element analysis (FEA) results are in good agreement with the experimental results. The results show that as the wind speed increases, the BHSL transitions from a single-well vibration response to a cross-well vibration response. The wind-induced vibration analysis of BHSL will provide analytical methods for its application in deformable wings and energy harvesting for wind-induced vibration. [ABSTRACT FROM AUTHOR]

This paper focuses on a study of the snap-through behavior of a family of bi-stable plates constructed by hybrid symmetric laminates with a cantilever boundary. Involving shape change and actuation demand, a deep understanding of the snap-through behavior is of particular importance since this bi-stable laminate is often served as a host structure of energy harvester or a morphing structure. The snap-through behavior is obtained using two displacement-controlled finite element procedures provided in the commercial software ABAQUS and the results are verified by experiments. The entire equilibrium path of reaction force-displacement response with a couple of zero load crossings is captured by the 'Static, Riks' procedure to reveal the potential nonlinear structural behavior. The practical situation of the reaction force-displacement curve is obtained by the 'Static, General' procedure which exhibits consistent results with experiments. Several characteristics, such as snap-down, hysteresis, negative stiffness, and even zero stiffness are captured. A parametric study including lay-up design and length is also carried out using the finite element model and verified by experiments. The results show that the lay-up design not only can fundamentally change the snap-through response but also influences other characteristics of this bi-stable laminate including stable shape, and the length is a relatively reliable parameter to alter the snap-through features, e.g. peak force and hysteresis performance. [ABSTRACT FROM AUTHOR]

The resulting oscillation of bi-stable hybrid symmetric laminate could enable broadband energy harvesting via piezoelectric transduction. The aim of this work is to investigate its dynamic behaviors to provide the basis for designing broadband energy harvester. This paper proposes the dynamic analysis of this bi-stable laminate, focusing on the intra-well dynamics around its stable states and the inter-well dynamics between two stable states. Two types of stacking sequence are performed for this bi-stable laminate, and experimental testing with different harmonic excitations is carried out for each type of this bi-stable laminate. The strain responses at three positions are monitored to investigate the dynamic responses. A finite element model is also developed to analyze the static strain distribution and capture the dynamics. The results show that the laminates exhibit intra-well response under low-level excitation, and the inter-well response at a particular range frequency appears when excitation level increases. Different types of inter-well response mode involving the snap-through behavior are obtained in experiments, such as intermittent inter-well vibration and chaotic vibration. The presented results essentially highlight the need for considering the stacking sequence associated with the dynamics while designing the hybrid bi-stable symmetric laminate to obtain the desirable nonlinear response. [ABSTRACT FROM AUTHOR]

This paper presents a multistable variable cross-section laminate (MVCL), which is designed by applying the displacement constraint at the two opposing ends of the laminate. A theoretical model describing the MVCL as rigid bars connected with compliant hinges is built to predict the equilibrium configurations and snap-through loads of the MVCL. The snap-through process of the multistable structure is investigated via experiment and finite element analysis (FEA). Subsequently, the theoretical model is improved by simplifying the middle segment of the MVCL as an elastic beam. Good agreement is obtained between the experimental test, FEA, and improved theoretical model results. It is shown that the current approach can be successfully applied to predict the equilibrium configurations and snap-through loads of an MVCL. The snap-through loads can be adjusted by changing the middle segment length of an MVCL. [ABSTRACT FROM AUTHOR]