Characterizing the Effective Bandwidth of Tri-Stable Energy Harvesters

2016 ◽  
Author(s):  
Meghashyam Panyam ◽  
Mohammed F. Daqaq
Keyword(s):  
Magnetic Field ◽  
Analytical Solutions ◽  
Energy Harvester ◽  
Multiple Scales ◽  
Method Of Multiple Scales ◽  
Experimental Studies ◽  
Effective Bandwidth ◽  
Frequency Bandwidth ◽  
Effective Frequency ◽  
Energy Harvesters

This paper aims to investigate the response and characterize the effective frequency bandwidth of tri-stable vibratory energy harvesters. To achieve this goal, the method of multiple scales is utilized to construct analytical solutions describing the amplitude and stability of the intra- and inter-well dynamics of the harvester. Using these solutions, critical bifurcations in the parameter’s space are identified and used to define an effective frequency bandwidth of the harvester. A piezoelectric tri-stable energy harvester consisting of a uni-morph cantilever beam is considered. Stiffness nonlinearities are introduced into the harvesters design by applying a static magnetic field near the tip of the beam. Experimental studies performed on the harvester are presented to validate some of the theoretical findings.

A Broadband Energy Harvester With Internal Resonance Induced by Two Resonators

2017 ◽  
Author(s):  
Wei Yang ◽  
Shahrzad Towfighian
Keyword(s):  
Frequency Response ◽  
Analytical Solutions ◽  
Internal Resonance ◽  
Output Voltage ◽  
Shooting Method ◽  
Energy Harvester ◽  
Multiple Scales ◽  
Method Of Multiple Scales ◽  
Ambient Vibrations ◽  
Nonlinear Energy

Nonlinear energy harvesting has a better performance than linear resonators, because realistic ambient vibrations are spread over a wide frequency spectrum. We present a broadband nonlinear energy harvester with internal resonance induced by two resonators. Each resonator contains a cantilever beam with a magnet tip, and one is partially covered by piezoelectric material. The perturbation method of multiple scales is used to solve coupled partial different equations by applying internal resonance of ratio 2:1. The shooting method validates the analytical solutions of the frequency response and output voltage numerically. Output voltage for different excitation levels and distances are investigated. Simulations show the design, by applying internal resonance and nonlinearity, increases the bandwidth of frequency response.

Enhanced frequency synchronization for concurrent aeroelastic and base vibratory energy harvesting using a softening nonlinear galloping energy harvester

2021 ◽  
pp. 1045389X2110263
Author(s):  
Shun Chen ◽  
David Eager ◽  
Liya Zhao
Keyword(s):  
Energy Harvesting ◽  
Electromechanical Coupling ◽  
Energy Harvester ◽  
Poor Performance ◽  
Effective Bandwidth ◽  
Frequency Synchronization ◽  
Periodic Oscillations ◽  
Energy Harvesters ◽  
Paper Form ◽  
Excited Oscillation

This paper proposes a softening nonlinear aeroelastic galloping energy harvester for enhanced energy harvesting from concurrent wind flow and base vibration. Traditional linear aeroelastic energy harvesters have poor performance with quasi-periodic oscillations when the base vibration frequency deviates from the aeroelastic frequency. The softening nonlinearity in the proposed harvester alters the self-excited galloping frequency and simultaneously extends the large-amplitude base-excited oscillation to a wider frequency range, achieving frequency synchronization over a remarkably broadened bandwidth with periodic oscillations for efficient energy conversion from dual sources. A fully coupled aero-electro-mechanical model is built and validated with measurements on a devised prototype. At a wind speed of 5.5 m/s and base acceleration of 0.1 g, the proposed harvester improves the performance by widening the effective bandwidth by 300% compared to the linear counterpart without sacrificing the voltage level. The influences of nonlinearity configuration, excitation magnitude, and electromechanical coupling strength on the mechanical and electrical behavior are examined. The results of this paper form a baseline for future efficiency enhancement of energy harvesting from concurrent wind and base vibration utilizing monostable stiffness nonlinearities.

Rayleigh–Taylor instability of a plasma in a magnetic field: nonlinear theory

1982 ◽  
Vol 27 (1) ◽  
pp. 129-134 ◽  
Author(s):  
Bhimsen K. Shivamoggi
Keyword(s):  
Magnetic Field ◽  
Nonlinear Analysis ◽  
Linear Theory ◽  
Nonlinear Theory ◽  
Multiple Scales ◽  
Method Of Multiple Scales ◽  
Taylor Instability ◽  
Rayleigh Taylor Instability ◽  
Linear Cut

Kaira & Kathuria used the method of multiple scales to develop nonlinear analysis of Rayleigh–Taylor instability of a plasma in a magnetic field. Their calculations remain valid only for wavenumbers k away from the linear cut-off value kc, and break down for wavenumbers near kc. The purpose of this paper is to treat the latter case. The solution uses the method of strained parameters. The results show the instability persists even at k = kc, despite the cut-off predicted by the linear theory.

Broadband and Enhanced Energy Harvesting Using Inerter Pendulum Vibration Absorber

2020 ◽  
Author(s):  
Aakash Gupta ◽  
Wei-Che Tai
Keyword(s):  
Large Scale ◽  
Multiple Scales ◽  
Equations Of Motion ◽  
Primary Resonance ◽  
Vibration Absorber ◽  
Frequency Bandwidth ◽  
Energy Harvesters ◽  
New Type ◽  
Electrical Damping ◽  
Relationship Of

Abstract Inerter-based vibration energy harvesters (VEHs) have been widely studied to harvest energy from large-scale structural vibrations. Recently, there have been efforts to increase the operation frequency bandwidth of VEHs by introducing a variety of stiffness and inertia nonlinearity. This paper proposes a new inerter-based VEH comprising an epicyclic-gearing inerter and a pendulum vibration absorber. The centrifugal force of the pendulum introduces a new type of inertia nonlinearity that broadens the frequency bandwidth. This inerter-pendulum VEH (IPVEH) is incorporated in a single-degree-of-freedom structure to demonstrate its performance and the equations of motion of the system are derived. The method of multiple scales is applied to derive the amplitude–frequency response relationship of the harvested power in the primary resonance. The harvested power is optimized through tuning the harvester’s electrical damping and the optimum power is benchmarked with that of conventional linear inerter-based VEHs. The results show that the IPVEH has larger bandwidth and harvested power and the improvement is correlated with the strength of its inertia nonlinearity.

Explosive Instability in Superposed Fluids in Hydromagnetics

1995 ◽  
Vol 50 (2-3) ◽  
pp. 125-130
Author(s):  
Gurpreet K. Gill ◽  
S. K. Trehan
Keyword(s):  
Magnetic Field ◽  
Flow Model ◽  
Multiple Scales ◽  
Method Of Multiple Scales ◽  
Density Ratio ◽  
Finite Amplitude ◽  
High Rate ◽  
Explosive Instability ◽  
Superposed Fluids ◽  
Very High

Abstract We study the resonance interaction between two marginally unstable modes of small but finite amplitude waves in the Kelvin-Helmholtz flow model using the method of multiple scales. We find that, as magnetic field increases, the amplitudes of the disturbance diverge at a very high rate while for a fluid of higher density ratio e, the amplitudes diverge very slowly.

scholarly journals An E-shape broadband piezoelectric energy harvester induced by magnets

2018 ◽  
Vol 29 (11) ◽  
pp. 2477-2491 ◽  
Author(s):  
Qingqing Lu ◽  
Fabrizio Scarpa ◽  
Liwu Liu ◽  
Jinsong Leng ◽  
Yanju Liu
Keyword(s):  
Broad Spectrum ◽  
Output Voltage ◽  
Energy Harvester ◽  
Variation Principle ◽  
Frequency Bandwidth ◽  
Restoring Force ◽  
Energy Harvesters ◽  
Piezoelectric Energy ◽  
Half Power ◽  
Tip Mass

We describe in this work a broadband magnetic E-shape piezoelectric energy harvester with wide frequency bandwidth. We develop first a nonlinear electromechanical model of the harvester based on the Hamilton variation principle that simulates the effect of the nonlinear magnetic restoring force at different spacing distances. The model is used to identify the distances existing between two different magnets that enable the system to perform with a specific nonlinearity. The performance of the E-shape piezoelectric energy harvester is also investigated through experiments, with E-shape energy harvesters at different spacing distances tested under several base acceleration excitations. We observe that the frequency domain output voltage of the system shows a general excellent controllable performance, with a widening of the frequency bandwidth. The half-power bandwidth of the linear energy harvester for a distance of 25 mm is 0.8 Hz only, which can be expanded to 2.67 Hz for the larger distance of 11 mm between magnets. The energy harvester presented in this work shows promising performances for broad-spectrum vibration excitations compared to conventional cantilever piezoelectric energy harvester systems with a tip mass.

Second Harmonic Resonance on the Surface of a Magnetohydrodynamic Fluid Column

1999 ◽  
Vol 54 (5) ◽  
pp. 335-342
Author(s):  
Doo-Sung Lee
Keyword(s):  
Magnetic Field ◽  
Multiple Scales ◽  
Method Of Multiple Scales ◽  
Second Harmonic ◽  
Numerical Results ◽  
Dynamical Equations ◽  
Weakly Nonlinear ◽  
Progressive Waves ◽  
Harmonic Resonance ◽  
Magnetohydrodynamic Fluid

The method of multiple scales is used to analyse the second harmonic resonance of weakly nonlinear progressive waves on the surface of a fluid column in the presence of a magnetic field. The dynamical equations governing the second harmonic resonance are obtained. Numerical results are given graphically.

scholarly journals Analytical and Experimental Studies of Double Elastic Steel Sheet (DESS) Vibration Energy Harvester System

Energies ◽  
2020 ◽  
Vol 13 (7) ◽  
pp. 1793
Author(s):  
Yi-Ren Wang ◽  
Ming-Syun Wong ◽  
Bo-Yan Chen
Keyword(s):  
Steel Sheet ◽  
Energy Harvester ◽  
Multiple Scales ◽  
Collection Efficiency ◽  
Perturbation Technique ◽  
Experimental Studies ◽  
Electric Energy ◽  
Vibration Energy ◽  
Vibration Energy Harvester ◽  
Piezoelectric Energy

This study provides a double elastic steel sheet (DESS) piezoelectric energy harvester system, in which the vibration generated by the deformation and clap of two elastic steel sheets is assisted by a piezo patch to generate electric energy. The system is combined with energy storage equipment to propose a complete solution forgreen energy integration. This study buildsexperimentallyon the model of the proposed system to explore its voltage, power output and energy collection efficiency. This study also builds atheoretical model of a nonlinear beam with the piezo patch, including the piezoelectric coupling coefficient and current equation. This nonlinear problem is analyzed by the method of multiple scales (MOMS). The system frequency response wasobserved using fixed points plots. The perturbation technique and numerical method wereused to mutually validate the experimental results; the concept of DESS vibration energy harvester (DESS VEH) is proved feasible. In order to prolong the lifetime of the clapping of DESS piezo patch, a camber protector design is proposed. The findings show that the power-generating effect is best when the piezo patch is placed at the peak of the third mode of the DESS system, and the high camber protector is used to generate electric energy.

Nonlinear Waves on the Surface of a Magnetohydrodynamic Fluid Column

2001 ◽  
Vol 56 (8) ◽  
pp. 585-595 ◽  
Author(s):  
Doo-Sung Lee
Keyword(s):  
Magnetic Field ◽  
Nonlinear Waves ◽  
Multiple Scales ◽  
Method Of Multiple Scales ◽  
Modulational Instability ◽  
Numerical Results ◽  
Nonlinear Propagation ◽  
Graphical Form ◽  
Propagation Of Waves ◽  
Magnetohydrodynamic Fluid

Abstract The method of multiple scales is used to analyse the nonlinear propagation of waves on the surface of a fluid column in the presence of a magnetic field. The evolution of the amplitude is governed by a nonlinear Schrödinger equation which gives the criterion for modulational instability. Numerical results are given in graphical form

The Experimental Study on a Bistable Piezoelectric-Electromagnetic Combined Vibration Energy Harvester

2017 ◽  
Author(s):  
Ming Hui Yao ◽  
Peng Fei Liu ◽  
Wei Zhang ◽  
Dong Xing Cao
Keyword(s):  
Power Generation ◽  
Cantilever Beam ◽  
Nonlinear Dynamic ◽  
Energy Harvester ◽  
Maximum Output ◽  
Frequency Bandwidth ◽  
Effective Frequency ◽  
Generation Efficiency ◽  
Dynamic Behaviors ◽  
Piezoelectric Cantilever

This paper presents an experimental investigation on the bistable piezoelectric electromagnetic combined energy harvester based on vibration. The end of the piezoelectric cantilever beam has a tip magnet. The opposite of the piezoelectric cantilever beam has a coil, a spring and a magnet. The power generation efficiency and dynamic behaviors for three different kinds of the piezoelectric cantilever beam structures are experimentally studied, such as the conventional piezoelectric cantilever beam, the bistable piezoelectric cantilever beam introduced spring and magnet, and the bistable piezoelectric cantilever beam introduced spring, magnet and coil. Experimental results show that the introduction of the spring and magnet improves the maximum output voltage and broaden the effective frequency bandwidth. The power generation efficiency of the system is improved by adding the coil. Complicated nonlinear dynamic behaviors occur in the system, when the spring and the magnet are introduced. These nonlinear dynamic behaviors broaden the effective frequency bandwidth.

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