Ramzan, Muhammad

The effect of flexibly mounted piezoelectric eel on energy harvesting in the wake of a circular cylinder / Muhammad Ramzan - 61p. Soft Copy 30cm

The current method of producing energy from non-renewable sources may soon come to an
end due to the ever-increasing demand for fossil fuels and the implications of escalating
global warming. For microelectromechanical systems that only need a few watts of power to
operate, an energy harvesting method based on wake flow energy is suggested. When a
piezoelectric flag is employed as a cantilever beam and positioned in the wake of a bluff
body, the strain exerted in the eel and the electrical voltage generated are ample to operate
underwater sensors. The goal of this research is to present an efficient, simple, and resilient
energy harvester that uses flow generated oscillations in response to ambient flow and fluidstructure interaction of flexibly mounted piezoelectric eel (pivoted mechanism) with inverted
c-shape cylinder. Research objectives are to study the effect of spring stiffness and Gz (Gap
along z-axis) on energy harvesting with varying Velocity. It was concluded from the research
that by increasing the spring stiffness Ks i.e., 0.005-0.07 N/mm, velocity from 0.18m/s to
0.36m/s at Gz = 6 results in highest frequency of 0.0887Hz, amplitude to length ratio of
1.4361, and maximum amount of output power 9.25uW.Minimum values were obtained at
bottom level of flow at Gz = 10, lower spring stiffness i.e., Ks=0.005 N/mm and lowest flow
velocity of 0.18 m/s. While comparing the results with previous studies i.e., Circular, and
inverted c-shape cylinder with mechanism of non-pivoted flag, significant amount of
increment is observed in flapping frequency, amplitude to length ratio and output power
which is 5.47%, 34.13% and 61.12% respectively.


MS Mechanical Engineering

621