Experimental hydrodynamic investigations on the effectiveness of inverted flag-based piezoelectric energy harvester in the wake of bluff body

2022 ◽  
Vol 245 ◽  
pp. 110454
Author(s):  
M. Umair ◽  
U. Latif ◽  
E. Uddin ◽  
A. Abdelkefi
Keyword(s):  
Bluff Body ◽  
Energy Harvester ◽  
Piezoelectric Energy

Modeling and Experimental Validations of a Piezoelectric Energy Harvester Under Combined Galloping and Base Excitations

2014 ◽  
Author(s):  
Amin Bibo ◽  
Abdessattar Abdelkefi ◽  
Mohammed F. Daqaq
Keyword(s):  
Bluff Body ◽  
Energy Harvester ◽  
Constitutive Relations ◽  
Excitation Frequency ◽  
Primary Resonance ◽  
Beam Theory ◽  
Excitation Amplitude ◽  
The Body ◽  
Base Excitation ◽  
Piezoelectric Energy

This paper develops an experimentally validated model of a piezoelectric energy harvester under combined aeroelastic-galloping and base excitations. To that end, an energy harvester consisting of a thin piezoelectric cantilever beam subjected to vibratory base excitation is considered. To permit galloping excitation, a bluff body is rigidly attached at the free end such that a net aerodynamic lift is generated as the incoming airflow separates on both sides of the body giving rise to limit cycle oscillations when the flow velocity exceeds a critical value. A nonlinear electromechanical distributed-parameter model of the harvester under the combined excitation is derived using the energy approach and by adopting the nonlinear Euler-Bernoulli beam theory, linear constitutive relations for the piezoelectric transduction, and the quasi-steady assumption for the aerodynamic loading. The partial differential equations of the system are discretized and a reduced-order-model is obtained. The mathematical model is validated by conducting a series of experiments with different loading conditions represented by wind speed, base excitation amplitude, and excitation frequency around the primary resonance.

Synchronization of Cantilevers Arranged in Line of a Piezoelectric Energy Harvester

2015 ◽  
Author(s):  
Max Spornraft ◽  
Norbert Schwesinger ◽  
Shlomo Berger
Keyword(s):  
Energy Harvesting ◽  
Bluff Body ◽  
Energy Harvester ◽  
Phase Synchronization ◽  
Vibrational Excitation ◽  
Line Energy ◽  
Mechanical Coupling ◽  
Piezoelectric Energy ◽  
Piezoelectric Cantilever ◽  
The Right

Synchronization opens further ways to improve cantilever-based energy harvesting arrays in view of power output, easier rectification and scaling. Objective of this study is to investigate the synchronization behavior of a cantilever-array based energy harvesting systems. Thereby, synchronization is achieved by mechanical coupling through a so-called “overhang”. Nakajima et al. [1] and Wang et al. [2] already verified this principle for the synchronization of two and three cantilevers, but at constant vibrational excitation. Regarding energy harvesting, no application of this method is presently available. In this paper, we investigate the synchronization behavior of a piezoelectric cantilever-line energy harvester in airflow. The design of the energy harvester bases upon a piezoelectric cantilever-line and a common bluff body, arranged upstream. To investigate synchronization of the cantilevers, three commonly available piezoelectric bimorphs were employed to study synchronization. Mounted on a common bluff body, the effect of overhang material and position was studied. Therefore, different constellations were examined by impulse excitation as well as vortex-induced vibration in a wind channel. In several measurements, we found arrangements and parameters allowing for an in-phase synchronization of neighborly cantilevers of the line. The knowledge gained allows for a direct electrical connection of piezoelectric cantilevers with just one single rectifier unit. Cantilevers coupled with overhangs arranged in the right order oscillate with the same frequency and phase, i.e. without any charge cancellations. This knowledge opens ways to develop basic design rules for the synchronization of cantilevers.

An enhanced hybrid piezoelectric–electromagnetic energy harvester using dual-mass system for vortex-induced vibrations

2021 ◽  
pp. 107754632110418
Author(s):  
Asan GA Muthalif ◽  
Muhammad Hafizh ◽  
Jamil Renno ◽  
Mohammad R Paurobally
Keyword(s):  
Bluff Body ◽  
Energy Harvester ◽  
Fiber Composite ◽  
Body Movement ◽  
Secondary Beam ◽  
Element Analysis ◽  
Mass System ◽  
Hybrid Energy ◽  
Piezoelectric Energy ◽  
Electromechanical Transduction

This article proposes a novel hybrid piezoelectric–electromagnetic vortex-induced vibration energy harvester from flow of water inside of a pipe. The piezoelectric energy harvester was modeled with a macro-fiber composite P2-type while the electromechanical transduction was modeled by an elastic magnet coupled to the bluff body movement. A dual-mass configuration was proposed to increase the energy harvesting efficiency. Theoretical models and the submerged natural frequencies of the hybrid energy harvesters were outlined. Computational fluid dynamics and finite element analysis with ANSYS were used to visualize the response in synchronization and output the voltage extracted from the harvesting mechanisms. The addition of a secondary system improves the amount of harvestable energy and outputs more energy than just a single system. This demonstrates the superiority of a dual-mass hybrid system. A tuned secondary beam was used for L-body configurations to make use of inline oscillations, and the secondary piezoelectric output improved for all configurations. Secondary beam tuning also improved the performance of the harvester by any amount between 21% and 52% when compared against a single-mass hybrid energy harvester. A comparative study showed that the L-vertical and vertical bluff-body-tuned was the best performing hybrid-PE energy harvester based on total voltage output.

Modeling and Characterization of a Piezoelectric Energy Harvester Under Combined Aerodynamic and Base Excitations

2015 ◽  
Vol 137 (3) ◽  
Author(s):  
Amin Bibo ◽  
Abdessattar Abdelkefi ◽  
Mohammed F. Daqaq
Keyword(s):  
Bluff Body ◽  
Energy Harvester ◽  
Constitutive Relations ◽  
Equations Of Motion ◽  
Primary Resonance ◽  
Beam Theory ◽  
Combined Loading ◽  
Response Behavior ◽  
Piezoelectric Energy ◽  
Piezoelectric Cantilever

This paper develops and validates an aero-electromechanical model which captures the nonlinear response behavior of a piezoelectric cantilever-type energy harvester under combined galloping and base excitations. The harvester consists of a thin piezoelectric cantilever beam clamped at one end and rigidly attached to a bluff body at the other end. In addition to the vibratory base excitations, the beam is also subjected to aerodynamic forces resulting from the separation of the incoming airflow on both sides of the bluff body which gives rise to limit-cycle oscillations when the airflow velocity exceeds a critical value. A nonlinear electromechanical distributed-parameter model of the harvester under the combined excitations is derived using the energy approach and by adopting the nonlinear Euler–Bernoulli beam theory, linear constitutive relations for the piezoelectric transduction, and the quasi-steady assumption for the aerodynamic loading. The resulting partial differential equations of motion are discretized and a reduced-order model is obtained. The mathematical model is validated by conducting a series of experiments at different wind speeds and base excitation amplitudes for excitation frequencies around the primary resonance of the harvester. Results from the model and experiment are presented to characterize the response behavior under the combined loading.

Performance of Galloping Piezoelectric Energy Harvesters With Square Bluff Body

2013 ◽  
Author(s):  
Felix Ewere ◽  
Gang Wang
Keyword(s):  
Experimental Data ◽  
Wind Tunnel ◽  
Mechanical Model ◽  
Bluff Body ◽  
Energy Harvester ◽  
Approximate Solutions ◽  
Wind Tunnel Tests ◽  
Energy Harvesters ◽  
Piezoelectric Energy ◽  
Physical Insight

In this paper, we investigate a galloping piezoelectric energy harvester (GPEH) with a square bluff body. Comprehensive wind tunnel tests are conducted and experimental data are used to validate our analytical approximate solutions, which are derived from a coupled aero-electro-mechanical model. In addition, the effects of impact disturbances using a bump are investigated. The goal is to improve the performance of baseline GPEH. We expect to collect physical insight to design an optimal nonlinear GPEH configuration by placing bumps accordingly. Lessons learnt from this study will be used to improve the performance of future nonlinear GPEHs and lead to a practical device.

scholarly journals Simulation and analysis of the aeroelastic-galloping-based piezoelectric energy harvester utilizing FEM and CFD

2018 ◽  
Vol 159 ◽  
pp. 01052
Author(s):  
Ismoyo Haryanto ◽  
Achmad Widodo ◽  
Toni Prahasto ◽  
Djoeli Satrijo ◽  
Iswan Pradiptya ◽  
...  
Keyword(s):  
Bluff Body ◽  
Energy Harvester ◽  
Electrical Power ◽  
Oscillation Amplitude ◽  
Dynamic Strain ◽  
Plane Normal ◽  
Piezoelectric Energy ◽  
Piezoelectric Cantilever ◽  
Cantilever Structure ◽  
Lift And Drag

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.

scholarly journals A Piezoelectric and Electromagnetic Hybrid Galloping Energy Harvester with the Magnet Embedded in the Bluff Body

Micromachines ◽  
2021 ◽  
Vol 12 (6) ◽  
pp. 626
Author(s):  
Xia Li ◽  
Cheng Bi ◽  
Zhiyuan Li ◽  
Benxue Liu ◽  
Tingting Wang ◽  
...  
Keyword(s):  
Numerical Simulation ◽  
Wind Speed ◽  
Output Power ◽  
Bluff Body ◽  
Energy Harvester ◽  
Electromagnetic Energy ◽  
Piezoelectric Energy ◽  
Field Lines ◽  
Output Characteristics ◽  
Effective Output

To meet the needs of low-power microelectronic devices for on-site self-supply energy, a galloping piezoelectric–electromagnetic energy harvester (GPEEH) is proposed. It consists of a galloping piezoelectric energy harvester (GPEH) and an electromagnetic energy harvester (EEH), which is installed inside the bluff body of the GPEH. The vibration at the end of the GPEH cantilever drives the magnet to vibrate, so that electromagnetic energy can be captured by cutting off the induced magnetic field lines. The coupling structure is a two-degree-of-freedom motion, which improves the output power of the energy harvester. Based on Hamilton’s variational principle and quasi-static hypothesis, the piezoelectric–electromagnetic vibrated coupling equation is established, and the output characteristics of GPEEH are obtained by the method of numerical simulation. Using the method of numerical simulation, studies a series of parameters on the output performance. when the wind speed is 9 m/s, the effective output power of the GPEEH is compared with the classical galloping piezoelectric energy harvester (CGPEH) who is no magnet. It is found that the output power of GPEEH 121% higher than the output power of CGPEH. Finally, set up an experimental platform, and test and verify. The experimental analysis results show that the simulated output parameter curves are basically consistent with the experimental drawing curves. In addition, when the wind speed is 9 m/s, under the same parameters, the effective output power of the GPEEH is 112.5% higher than that of the CGPEH. The correctness of the model is verified.

Sign in / Sign up

Export Citation Format

Share Document