Comprehensive study of fluid-structure interaction in vortex-induced vibrations: Integration of experimental, computational and wake oscillator approaches

Najafpour, Alireza; Rajabi, Matin; Esmaeili, Mostafa; Rabiee, Amir Hossein

doi:10.22064/tava.2025.2043193.1255

Comprehensive study of fluid-structure interaction in vortex-induced vibrations: Integration of experimental, computational and wake oscillator approaches

Document Type : H. Ahmadian Prize

Authors

Alireza Najafpour ¹

Matin Rajabi ¹

Mostafa Esmaeili ¹

Amir Hossein Rabiee ²

¹ Department of Mechanical Engineering, Kharazmi University, 15719-14911, Tehran, IRAN.

² School of Mechanical Engineering, Arak University of Technology, 38181-41167, Arak, IRAN

10.22064/tava.2025.2043193.1255

Abstract

This research explores the potential of vortex-induced vibration (VIV) as a viable renewable energy source for harvesting low-speed wind energy, particularly for low-power sensors utilized in structural health monitoring. By integrating experimental methods, mathematical modelling through the wake oscillator model, and computational fluid dynamics (CFD) simulations, we present a holistic examination of fluid-structure interaction (FSI) in the context of energy generation. The experimental phase involved an elastically mounted circular cylinder positioned on an aluminium beam inside a wind tunnel, where the Reynolds number varied from 4,100 to 11,500. The cylinder's motion was limited to the transverse direction, leading to significant findings within the lock-in region—characterized by the highest amplitudes of vibration and, correspondingly, the greatest power output. Our data indicated that increased oscillation amplitudes enhanced piezoelectric voltage and power output, primarily due to increased strain within the piezoelectric layers. The peak output voltage was recorded at a reduced velocity (Ur) of 5.7, while the optimal load resistance for energy extraction was determined to be 6.56 MΩ based on repeated experimental trials. Mathematical modelling was then implemented, bringing a deeper phenomenological understanding through the wake oscillator model, which could effectively explain the lock-in range and amplitude of experimental data. Moreover, numerical simulations utilizing the SST k–ω turbulence model further contributed insights into the vortex dynamics behind the cylinder and their response to varying flow speeds.

Highlights

Wind tunnel is utilized to explore VIV’s potential for energy harvesting.
Fluid-structure interaction analysis for energy harvesting is performed.
Highest piezoelectric voltage / power were observed in the lock-in region.
Peak output voltage was recorded at 5.7 m/s velocity and 6.56 MΩ load resistance.

Keywords

Vortex-Induced Vibration (VIV)

Energy harvesting

Circular cylinder

Wake oscillator model

Computational fluid dynamics (CFD)