Experimental Study of a Self-Excited Piezoelectric Energy Harvester

Author(s):  
Hu¨seyin Dog˘us¸ Akaydın ◽  
Niell Elvin ◽  
Yiannis Andreopoulos

In the present experimental work, we explore the possibility of using piezoelectric based fluid flow energy harvesters. These harvesters are self-excited and self-sustained in the sense that they can be used in steady uniform flows. The configuration consists of a piezoelectric cantilever beam with a cylindrical tip body which promotes sustainable, aero-elastic structural vibrations induced by vortex shedding and galloping. The structural and aerodynamic properties of the harvester alter the vibration amplitude and frequency of the piezoelectric beam and thus its electrical output. This paper presents results of energy-harvesting tests with one configuration of such a self-excited piezoelectric harvester using a PZT bimorph. In addition to the electrical voltage output, the strain on the surface of beam close to its clamped tip was also measured The measured strain and voltage output were perfectly correlated in the frequency range containing the first natural mode of vibration of the system. It was observed that about 0.24 mW of electrical power can be attained with this harvester in a uniform flow of 28 m/s.

2015 ◽  
Vol 23 (15) ◽  
pp. 2538-2553 ◽  
Author(s):  
Ahmed Jemai ◽  
Fehmi Najar ◽  
Moez Chafra

The use of a multilayer piezoelectric cantilever beam for vibration-based energy harvesting applications has been investigated as an effective technique to increase the harvested electrical power. It has been shown that the multilayered energy harvester performance is very sensitive to the number of layers and their electrical connection due to impedance variations. The objective of this work is to suggest a comprehensive mathematical model of multilayered unimorph piezoelectric energy harvester allowing analytical solution for the harvested voltage and electrical power. The model is used to deeply investigate the influence of different parameters on the harvested power. A distributed-parameter model of the harvester using the Euler–Bernoulli beam theory and Hamilton's principle is derived. Gauss's law is used to derive the electrical equations for parallel and series connections. A closed-form solution is proposed based on the Galerkin procedure and the obtained results are validated with a finite element 3D model. A parametric study is performed to ascertain the influence of the load resistance, the thickness ratio, the number of piezoelectric layers on the tip displacement and the electrical harvested power. It is shown that this model can be easily used to adjust the geometrical and electrical parameters of the energy harvester in order to improve the system's performances. In addition, it is proven that if one of the system's parameter is not correctly tuned, the harvested power can decrease by several orders of magnitude.


Author(s):  
P. B. Jain ◽  
M. R. Cacan ◽  
S. Leadenham ◽  
C. De Marqui ◽  
A. Erturk

The harvesting of flow energy by exploiting aeroelastic and hydroelastic vibrations has received growing attention over the last few years. The goal in this research field is to generate low-power electricity from flow-induced vibrations of scalable structures involving a proper transduction mechanism for wireless applications ranging from manned/unmanned aerial vehicles to civil infrastructure systems located in high wind areas. The fundamental challenge is to enable geometrically small flow energy harvesters while keeping the cut-in speed (lowest flow speed that induces persistent oscillations) low. An effective design with reduced cut-in speed is known to be the T-shaped cantilever arrangement that consists of a horizontal piezoelectric cantilever with a perpendicular vertical beam attachment at the tip. The direction of incoming flow is parallel to the horizontal cantilever and perpendicular to the vertical and symmetric tip attachment. Vortex-induced vibration resulting from flow past the tip attachment is the source of the aeroelastic response. For a given width of the T-shaped harvester with fixed thickness parameters, an important geometric parameter is the length ratio of the tip attachment to the cantilever. In this paper we investigate the effect of this geometric parameter on the piezoaeroelastic response of a T-shaped flow energy harvester. A controlled desktop wind tunnel system is used to characterize the electrical and mechanical response characteristics for broad ranges of flow speed and electrical load resistance using different vertical tip attachment lengths for the same horizontal piezoelectric cantilever. The variations of the electrical power output and cut-in speed with changing head length are reported along with an investigation into the electroaeroelastic frequency response spectra.


Author(s):  
Ali H. Alhadidi ◽  
Amin Bibo ◽  
Mohammed F. Daqaq

This ppppaper examines the performance of a galloping energy harvester possessing a nonlinear restoring force. To achieve this goal, a flow energy harvester consisting of a piezoelectric cantilever beam augmented with a square-sectioned bluff body at the free end is considered. Two magnets located near the tip of the bluff body are used to introduce the nonlinearity which strength and nature can be altered by changing the distance between the magnets. A lumped-parameter aero-electromechanical model adopting the quasi-steady assumption for aerodynamic loading is presented and utilized to numerically simulate the harvester’s response. Wind tunnel tests are also performed to validate the numerical simulations by conducting upward and downward wind velocity sweeps. Results comparing the relative performance of several harvesters with potential functions of different shapes demonstrate that a mono-stable potential function with a hardening restoring force can outperform all other configurations.


2012 ◽  
Vol 1397 ◽  
Author(s):  
Seon-Bae Kim ◽  
Jung-Hyun Park ◽  
Seung-Hyun Kim ◽  
Hosang Ahn ◽  
H. Clyde Wikle ◽  
...  

ABSTRACTA transverse (d33) mode piezoelectric cantilever was fabricated for energy harvesting. Various dimensions of interdigital electrodes (IDE) were deposited on a piezoelectric layer to examine the effects of electrode design on the performance of energy harvesters. Modeling was performed to calculate the output power of the devices. The estimation was based on Roundy’s analytical modeling derived for a d31 mode piezoelectric energy harvester (PEH). In order to apply the Roundy’s model to d33 mode PEH, the IDE configuration was converted to the area of top and bottom electrodes (TBE). The power conversion in d33 mode PEH was commonly estimated by the product of piezoelectric layer’s thickness and finger electrode’s length. In addition, the spacing between fingers was regarded as gap between top and bottom electrodes. However, the output power in a transverse mode PEH increases continuously with the increase of finger spacing, which does not correspond to experimental results. In this research, the dimension of IDE was converted to that of TBE using conformal mapping, and variation of power of PEH was remodeled. The modified model suggests that the maximum power in a transverse mode PEH is obtained when the finger spacing is identical with effective finger spacing. The output power then decreases when finger spacing is larger than effective finger spacing. The decrease of efficiency may result from insufficient degree of poling and increased charged defect with increasing finger spacing.


Author(s):  
Punnag Chatterjee ◽  
Matthew Bryant

This paper presents an initial experimental and computational investigation of a flow-induced vibration energy harvester with a compliant flexure mechanism. This energy harvester utilizes the aeroelastic flutter phenomenon to convert the flow energy to vibrational energy which can be converted into useful electrical power using piezoelectric transducers. However, unlike previous flutter-based flow energy harvesters [1] which require assembling multiple components to create the necessary aeroelastic arrangement, the device described here utilizes a monolithic, compact design to achieve the same. In this paper, we propose a flexure design for this device and model it using analytic methods and finite element simulations. A proof of concept energy harvester incorporating this flexure design has been fabricated and experimentally investigated in wind tunnel testing.


Author(s):  
James H. Noel ◽  
Mohammed F. Daqaq

Flow energy harvesters (FEHs) have recently emerged as a major player in the field of micro-power generation. Such devices are designed to harness energy from a dynamic flow field, typically wind, in order to power remote, sub-milliwatt consumption sensors that are hard to access or maintain. Previous research efforts have focused on harnessing flow energy under nearly steady conditions where measurable variations in the flow speed occur at a much longer time scale than the time constant of the harvester itself. Under such conditions, the nature of the harvester’s transient response is irrelevant and does not constitute a critical performance criterion. However, since gusts of wind also contain a significant amount of energy, designing FEHs to have a fast transient response is essential to capture the maximum possible energy from the flow. To address this critical issue, we propose a galloping piezoelectric energy harvester consisting of piezoelectric cantilever beam with a modified bluff body mounted at its tip. Square, trapezoid, and triangle bluff bodies were tested, each augmented with a tail fin to enhance the transient response of the harvester. It is shown experimentally that the settling time of the response and the steady state output power can be improved substantially when the fin is added.


Energies ◽  
2019 ◽  
Vol 12 (11) ◽  
pp. 2184 ◽  
Author(s):  
Ying Gong ◽  
Zhengbao Yang ◽  
Xiaobiao Shan ◽  
Yubiao Sun ◽  
Tao Xie ◽  
...  

Flow-induced energy harvesting has attracted more and more attention among researchers in both fields of the wind and the fluid. Piezoelectric energy harvesters and triboelectric nanogenerators are exploited to obtain superior performance and sustainability, and the electromagnetic conversion has been continuously improved in the meantime. Aiming at different circumstances, researchers have designed, manufactured, and tested a variety of energy harvesters. In this paper, we analyze the state-of-the-art energy harvesting techniques and categorize them based on the working environment, application targets, and energy conversion mechanisms. The trend of research endeavors is analyzed, and the advantages, existing problems of energy harvesters, and corresponding solutions of energy harvesters are assessed.


Sensors ◽  
2021 ◽  
Vol 21 (20) ◽  
pp. 6759
Author(s):  
Zdenek Machu ◽  
Ondrej Rubes ◽  
Oldrich Sevecek ◽  
Zdenek Hadas

This paper deals with analytical modelling of piezoelectric energy harvesting systems for generating useful electricity from ambient vibrations and comparing the usefulness of materials commonly used in designing such harvesters for energy harvesting applications. The kinetic energy harvesters have the potential to be used as an autonomous source of energy for wireless applications. Here in this paper, the considered energy harvesting device is designed as a piezoelectric cantilever beam with different piezoelectric materials in both bimorph and unimorph configurations. For both these configurations a single degree-of-freedom model of a kinematically excited cantilever with a full and partial electrode length respecting the dimensions of added tip mass is derived. The analytical model is based on Euler-Bernoulli beam theory and its output is successfully verified with available experimental results of piezoelectric energy harvesters in three different configurations. The electrical output of the derived model for the three different materials (PZT-5A, PZZN-PLZT and PVDF) and design configurations is in accordance with lab measurements which are presented in the paper. Therefore, this model can be used for predicting the amount of harvested power in a particular vibratory environment. Finally, the derived analytical model was used to compare the energy harvesting effectiveness of the three considered materials for both simple harmonic excitation and random vibrations of the corresponding harvesters. The comparison revealed that both PZT-5A and PZZN-PLZT are an excellent choice for energy harvesting purposes thanks to high electrical power output, whereas PVDF should be used only for sensing applications due to low harvested electrical power output.


2008 ◽  
Vol 20 (5) ◽  
pp. 529-544 ◽  
Author(s):  
Alper Erturk ◽  
Jamil M. Renno ◽  
Daniel J. Inman

Cantilevered piezoelectric energy harvesters have been extensively investigated in the literature of energy harvesting. As an alternative to conventional cantilevered beams, this article presents the L-shaped beam-mass structure as a new piezoelectric energy harvester configuration. This structure can be tuned to have the first two natural frequencies relatively close to each other, resulting in the possibility of a broader band energy harvesting system. This article describes the important features of the L-shaped piezoelectric energy harvester configuration and develops a linear distributed parameter model for predicting the electromechanically coupled voltage response and displacement response of the harvester structure. After deriving the coupled distributed parameter model, a case study is presented to investigate the electrical power generation performance of the L-shaped energy harvester. A direct application of the L-shaped piezoelectric energy harvester configuration is proposed for use as landing gears in unmanned air vehicle applications and a case study is presented where the results of the L-shaped — energy harvester — landing gear are favorably compared against the published experimental results of a curved beam configuration used for the same purpose.


2018 ◽  
Vol 159 ◽  
pp. 01052
Author(s):  
Ismoyo Haryanto ◽  
Achmad Widodo ◽  
Toni Prahasto ◽  
Djoeli Satrijo ◽  
Iswan Pradiptya ◽  
...  

Due to a large oscillation amplitude, galloping can be an admissible scenario to actuate the piezoelectric-based energy harvester. In the case of harvesting energy from galloping vibrations, a prismatic bluff body is attached on the free end of a piezoelectric cantilever beam and the oscillation occurs in a plane normal to the incoming flow. The electrical power then can be extracted from the piezoelectric sheet bonded in the cantilever structure due to the dynamic strain. This study is proposed to develop a theoretical model of a galloping-based piezoelectric energy harvester. A FEM procedure is utilized to determine dynamic characteristics of the structure. Whereas the aerodynamic lift and drag coefficients of the tip bluff body are determined using CDF. The results show that the present method gives precise results of the power generated by harvester. It was found that D-section yields the greatest galloping behavior and hence the maximum power.


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