scholarly journals Study of a Microbistable Piezoelectric Energy Harvesting

2018 ◽  
Vol 2018 ◽  
pp. 1-8 ◽  
Author(s):  
Li Hua Chen ◽  
Shou Jie Cui ◽  
Shuo Yang ◽  
Wei Zhang
Keyword(s):  
Energy Harvesting ◽  
Coupling Effect ◽  
Resonance Region ◽  
Strain Gradient Theory ◽  
Gradient Theory ◽  
Energy Capture ◽  
Piezoelectric Energy ◽  
Four Corners ◽  
Voltage Frequency ◽  
The Ideal

A microbistable piezoelectric energy harvester has been developed. The harvester was based on a center-fixed and quadrilateral-free microbistable plate with mass blocks placed at the four corners. Considering the thermoelectromechanical coupling effect, a nonlinear oscillation differential equation was established by Hamilton’s principle. Strain gradient theory was applied to consider the size effect, and von Karman theory was used to consider the large deformation effect. The influences of the laying position and area of the piezoelectric layer on the efficiency of energy capture were investigated. The voltage-frequency response of the nonlinear system was investigated, and the snap-through behavior of the bistable plate results in energy harvesting achieving the ideal broaden frequency range before the resonance region.

Tunable Energy Harvesting From Ambient Vibrations

2010 ◽  
Author(s):  
Mohamed Rhimi ◽  
Nizar Lajnef
Keyword(s):  
Energy Harvesting ◽  
Lead Zirconate Titanate ◽  
Coupling Effect ◽  
Energy Levels ◽  
Axial Loading ◽  
Lead Zirconate ◽  
Energy Scavenging ◽  
Ambient Vibrations ◽  
Civil Structures ◽  
Piezoelectric Energy

Most civil structures have a low vibration response frequency range, generally one to two orders of magnitude lower than the operating frequency spectrum of most piezoelectric energy scavenging devices, which is dictated by the device’s design and the used materials. This considerably limits the levels of harvestable power under ambient vibrations. In this paper, the improvement of the energy harvesting characteristics of a bimorph cantilever lead zirconate titanate (PZT) piezoelectric beam through the application of initial pre-stress loading conditions is studied. A generalized model that can take into account all the vibration modes of the beam as well as the back coupling effect is derived using the Hamiltonian principle. The model describes the effect of the pre-stress parameters on the harvestable energy levels. Results showing the variations of the natural frequency, amplitude, and efficiency of the piezoelectric device with varying preload are presented. Vibration recordings from a bridge under ambient loading are used to show variations of the harvested power with different pre-stress conditions. Increases of up to 250% in the output power levels are shown possible through the application of 8N of compressive axial loading for a system with a 15g vibrating mass. Experimental verification of the model is also performed. The time and frequency domain responses of a piezoelectric bimorph are measured and compared to theoretical results.

scholarly journals Experimental Research on Wind-Induced Flag-Swing Piezoelectric Energy Harvesters

2021 ◽  
Vol 2021 ◽  
pp. 1-8
Author(s):  
Jianjun Liu ◽  
Xianghua Chen ◽  
Yujie Chen ◽  
Hong Zuo ◽  
Qun Li
Keyword(s):  
Energy Harvesting ◽  
Cantilever Beam ◽  
Wind Field ◽  
Electromechanical Coupling ◽  
Energy Harvester ◽  
Coupling Effect ◽  
Green Energy ◽  
External Resistance ◽  
Piezoelectric Energy ◽  
Piezoelectric Cantilever

Piezoelectric cantilever beams, which have simple structures and excellent mechanical/electrical coupling characteristics, are widely applied in energy harvesting. When the piezoelectric cantilever beam is in a wind field, we should consider not only the influence of the wind field on piezoelectric beam but also the electromechanical coupling effect on it. In this paper, we design and test a wind-induced flag-swing piezoelectric energy harvester (PEH). The piezoelectric cantilever beam may vibrate in the wind field by affixing a flexible ribbon to the free end as the windward structure. To fulfill the goal of producing electricity, the flexible ribbon can swing the piezoelectric cantilever in a wind-induced unstable condition. The experimental findings demonstrate that the flag-swing PEH performs well in energy harvesting when the wind field is excited. When the wind speed is 15 m/s, the peak-to-peak output AC voltage may reach 13.88 V. In addition, the voltage at both ends of the closed-loop circuit’s external resistance is examined. The maximum electric power of the PEH may reach 43.4 μW with an external resistance of 650 kΩ. After passing through the AC-DC conversion circuit, the flag-swing PEH has a steady DC voltage output of 1.67 V. The proposed energy harvester transforms wind energy from a wind farm into electrical energy for supply to low-power electronic devices, allowing for the creation and use of green energy to efficiently address the issue of inadequate energy.

scholarly journals Simulating the Formation of Blasting-Excavation-Induced Zonal Integration in Deep Tunnels with an Elastoplastic Damage Model

2021 ◽  
Vol 2021 ◽  
pp. 1-18
Author(s):  
Qiang Gao ◽  
Chuanxiao Liu ◽  
Jian Zhang ◽  
Guangtan Cheng
Keyword(s):  
Coupling Effect ◽  
Damage Model ◽  
Morphological Characteristics ◽  
Numerical Approach ◽  
Surrounding Rock ◽  
Strain Gradient Theory ◽  
Zonal Disintegration ◽  
Gradient Theory ◽  
Blasting Excavation ◽  
Elastoplastic Damage

More deep tunneling projects will be constructed due to the increasing demand of underground energy and resource. The zonal disintegration phenomena are frequently encountered with the surrounding rock of deep tunnels. To explain the mechanisms underlying the formation of zonal disintegration, an elastoplastic damage model and failure criterion are proposed in this study based on the strain gradient theory and the damage property of rock mass. A coupling calculation subroutine is thereafter developed by the ABAQUS code. The dynamic formation and development regularity of zonal disintegration in the deep tunnel are simulated by this subroutine. The radial displacement, radial stress, and tangential stress show the oscillated variation of peaks and troughs alternately. The coupling effect of the blasting load and the initial geostress transient unloading leads to the variation of alternation oscillation in the surrounding rock stress field, which is an important reason for the zonal disintegration of the surrounding rock. The morphological characteristics of fractured zones and nonfractured zones obtained from numerical simulations are in good agreement with the results from the in situ observations, which confirm the correctness and feasibility of the damage and numerical approach. The method proposed in the current study can be utilized to provide a basis for the prediction and supporting design of fractured modes.

Investigation of efficient piezoelectric energy harvesting from impulsive force

2020 ◽  
Vol 59 (SP) ◽  
pp. SPPD04
Author(s):  
S. Aphayvong ◽  
T. Yoshimura ◽  
S. Murakami ◽  
K. Kanda ◽  
N. Fujimura
Keyword(s):  
Energy Harvesting ◽  
Piezoelectric Energy Harvesting ◽  
Impulsive Force ◽  
Piezoelectric Energy

scholarly journals Piezoelectric Energy Harvesting Solutions: A Review

Sensors ◽  
2020 ◽  
Vol 20 (12) ◽  
pp. 3512 ◽  
Author(s):  
Corina Covaci ◽  
Aurel Gontean
Keyword(s):  
Energy Harvesting ◽  
Piezoelectric Effect ◽  
Piezoelectric Transducers ◽  
Piezoelectric Energy Harvesting ◽  
Piezoelectric Energy ◽  
Direct Piezoelectric Effect ◽  
Harvesting Technique ◽  
Different Shapes ◽  
Piezoelectric Devices ◽  
Review Current

The goal of this paper is to review current methods of energy harvesting, while focusing on piezoelectric energy harvesting. The piezoelectric energy harvesting technique is based on the materials’ property of generating an electric field when a mechanical force is applied. This phenomenon is known as the direct piezoelectric effect. Piezoelectric transducers can be of different shapes and materials, making them suitable for a multitude of applications. To optimize the use of piezoelectric devices in applications, a model is needed to observe the behavior in the time and frequency domain. In addition to different aspects of piezoelectric modeling, this paper also presents several circuits used to maximize the energy harvested.

On size-dependent bending behaviors of shape memory alloy microbeams via nonlocal strain gradient theory

2021 ◽  
pp. 1045389X2098699
Author(s):  
Bo Zhou ◽  
Zetian Kang ◽  
Xiao Ma ◽  
Shifeng Xue
Keyword(s):  
Shape Memory Alloy ◽  
Shape Memory ◽  
Functionally Graded ◽  
Strain Gradient Theory ◽  
Gradient Theory ◽  
Size Dependent ◽  
Material Length Scale Parameter ◽  
Material Length Scale ◽  
Material Length ◽  
Nonlocal Strain Gradient

This paper focuses on the size-dependent behaviors of functionally graded shape memory alloy (FG-SMA) microbeams based on the Bernoulli-Euler beam theory. It is taken into consideration that material properties, such as austenitic elastic modulus, martensitic elastic modulus and critical transformation stresses vary continuously along the longitudinal direction. According to the simplified linear shape memory alloy (SMA) constitutive equations and nonlocal strain gradient theory, the mechanical model was established via the principle of virtual work. Employing the Galerkin method, the governing differential equations were numerically solved. The functionally graded effect, nonlocal effect and size effect of the mechanical behaviors of the FG-SMA microbeam were numerically simulated and discussed. Results indicate that the mechanical behaviors of FG-SMA microbeams are distinctly size-dependent only when the ratio of material length scale parameter to the microbeam height is small enough. Both the increments of material nonlocal parameter and ratio of material length-scale parameter to the microbeam height all make the FG-SMA microbeam become softer. However, the stiffness increases with the increment of FG parameter. The FG parameter plays an important role in controlling the transverse deformation of the FG-SMA microbeam. This work can provide a theoretical basis for the design and application of FG-SMA microstructures.

Sign in / Sign up

Export Citation Format

Share Document