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Energy harvesting from flow-induced vibrations has gained substantial attention in the last two decades due to the rising demand for renewable and sustainable energy sources, as well as the widely availability of these sources, offering a viable alternative in areas where other ambient energy sources may not be readily accessible. Flow-induced vibrations of bluff bodies are characterized by complex nonlinear dynamics, for which accurate models are currently lacking. In this work, a circular cylinder attached to the free end of a piezoelastic cantilever is considered for energy harvesting. When placed in a flow, this system undergoes vortex-induced vibrations. A reduced-order model is developed to understand fluid-structure interactions of this system. A wake oscillator has been used to describe vortex-induced vibrations and a finite-element model has been used to model the piezoelastic cantilever. The developed model is used to explore the interplay amongst the fluid, structure, and piezoelectric element. The results obtained are compared to experimental data from literature, in terms of the vibration amplitude, vibration frequency, and power obtained. Modifications to the wake oscillator model are examined to better reflect the fluid-structure interactions. It is found that there is a trade-off between accurately predicting the vibration amplitude and accurately predicting the vibration frequency.
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This content will become publicly available on December 2, 2025
Cantilevers attached with bluff bodies: vortex-induced vibrations
Vortex-induced vibrations are oscillatory motions experienced by a body interacting with an external flow. These vibrations can be harnessed for energy harvesting purpose. A cantilever beam with a cylinder attached at the free end represents the bluff body oscillator of interest here. Vortex-induced vibrations of two adjacent bluff-body oscillators are studied by varying the transverse spacing between the oscillators. A finite element model of the system is used to numerically study the associated fluid–structure interactions. For the case with two oscillators, the effect of varying the oscillator spacing on the system response is studied. Dynamic mode decomposition is used for extracting coherent spatio-temporal structures in pressure fields. The system spectral response for the single oscillator and coupled oscillators cases are studied to examine the system dynamics. The obtained numerical results for the system dynamics are found to agree with previously reported experimental results in the literature. The present work can form a basis for constructing computational models of fluid coupled bluff-body oscillators and configuring arrays of bluff-body oscillators for energy harvesting.
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- Award ID(s):
- 2131594
- PAR ID:
- 10603956
- Publisher / Repository:
- Springer
- Date Published:
- Journal Name:
- Nonlinear Dynamics
- ISSN:
- 0924-090X
- Subject(s) / Keyword(s):
- Vortex-induced vibrations Fluid–structure interactions Dynamic mode decomposition
- Format(s):
- Medium: X
- Sponsoring Org:
- National Science Foundation
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