Vibration based T-shaped piezoelectric cantilever beam design using finite element method for energy harvesting devices

The aim of this study is to develop structural strength analysis technique and real-time measuring system of composite laminate using finite element method (FEM) and fiber bragg grating (FBG) sensor. A composite laminate of cantilever beam was designed and fabricated using glass fiber reinforced plastic (GFRP) for structural mechanics behavior research. Six design cases of different orientations composite laminate were considered for the better combinations by using FEM program. The bending test of a composite laminate of cantilever beam was performed by using FBG sensor to obtained relationship between strain and displacement. The study result shows that the higher stiffness of composite laminate of cantilever beam was obtained in the [0/90/0/90] orientation. The first natural frequency is 34.83 Hz and corresponding mode shape is bending mode in Z-direction. The FEM and FBG sensor have been successfully used in variety of composite laminate design with different layering sequences by this article.

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Natural frequencies of a rotating curved cantilever beam: A perturbation method-based approach

Proceedings of the Institution of Mechanical Engineers Part C Journal of Mechanical Engineering Science ◽

10.1177/0954406219899117 ◽

2020 ◽

Vol 234 (9) ◽

pp. 1706-1719

Author(s):

Ajinkya Baxy ◽

Abhijit Sarkar

Keyword(s):

Finite Element Method ◽

Finite Element ◽

Perturbation Method ◽

Cantilever Beam ◽

Natural Frequencies ◽

Analytical Formula ◽

Industrial Applications ◽

Curved Beam ◽

Straight Beam ◽

Element Method

The blades of propellers, fans, compressor and turbines can be modeled as curved beams. In general, for industrial application, finite element method is employed to determine the modal characteristics of these structures. In the present work, a novel formula for determining the natural frequencies of a rotating circularly curved cantilever beam is derived. Rayleigh–Ritz approach is used along with perturbation method to obtain the analytical formula. In the first part of the work, a formula for natural frequencies of a non-rotating curved beam vibrating in its plane of curvature is presented. This formula is derived as a correction to the natural frequencies of its straight counterpart. The curvature is treated as a perturbation parameter. In the next part of the work, the effect of rotation on the curved beam is captured as an additional perturbation. Thus, the formula for a curved rotating beam is derived as a correction (involving two perturbation parameters) to the non-rotating straight beam. The results obtained using the derived formula are compared with the finite element method results. It is found that the frequency estimates from the formula are valid over a fairly large range of curvature and rotation speed. Thus, the derived formula can provide a faster alternative for design iterations in industrial applications.

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