Piezoelectric Actuated Nonlinear Energy Sink With Tunable Attenuation Efficiency

2019 ◽  
Vol 87 (2) ◽  
Author(s):  
Jian Zhao ◽  
Ming Lyu ◽  
Hongxi Wang ◽  
Najib Kacem ◽  
Yu Huang ◽  
...  
Keyword(s):  
Nonlinear Energy Sink ◽  
Mathematic Model ◽  
Threshold Value ◽  
Excitation Amplitude ◽  
Wide Frequency Range ◽  
Application Range ◽  
High Attenuation ◽  
Energy Pumping ◽  
Energy Sink ◽  
Nonlinear Energy

Abstract Comparing to linear vibration absorbers, nonlinear energy sinks (NESs) have attracted worldwide attention for their intrinsic characteristics of targeted energy transfer or energy pumping in a relatively wide frequency range. Unfortunately, they are highly dependent on the vibration amplitude to be attenuated and will play its role only if the external load exceeds a specific threshold value. Different from the passive bistable NES, a novel piezoelectric nonlinear energy sink (PNES) is designed by introducing in-phase actuation to compensate or enhance the external vibration loads, thus triggering the NES operating in high attenuation efficiency. The nonlinear mathematic model of the PNES is established for investigating the dynamic response and determining the threshold compensation strategy. And the results show that the maximum attenuation efficiency can be improved by 58.16% compared to the traditional passive NES. Also, the amplitude-dependent coefficient (ADC) can be significantly reduced to 0.33 from 1.0, which means that the PNES can effectively mitigate vibrations even when the excitation amplitude is 67% smaller than the original threshold value. Finally, the feasibility of the in-phase compensation method is experimentally validated, which can further expand the application range of NES.

Effects of bi-stable grounded nonlinear energy sink on energy dissipation of the system

2021 ◽  
pp. 146441932110460
Author(s):  
Arash Khalatbari ◽  
Amir Jalali ◽  
Habib Ahmadi ◽  
Kamran Foroutan
Keyword(s):  
Energy Dissipation ◽  
Total Energy ◽  
Invariant Manifolds ◽  
Equations Of Motion ◽  
Nonlinear Energy Sink ◽  
Multiple Scale ◽  
Excitation Amplitude ◽  
Energy Pumping ◽  
Energy Sink ◽  
Nonlinear Energy

In this paper, one of the most efficient passive absorbers, called nonlinear energy sink (NES), is analytically studied. A two-degree-of-freedom system is considered which consists of a linear oscillator (LO) with a base excitation and an NES, called grounded NES (GNES), which is connected to the ground with a nonlinear spring. In this study, we proposed a new arrangement of potential elements in GNES and studied invariant manifolds of the system, as well as the energy absorption performance of the NES. The system is considered in the vicinity of 1:1 resonance to investigate the strongly modulated response (SMR). To this end, after obtaining the equations of motion, the Manevitch complex variable and multiple scale method are applied to solve the equations, analytically. Then, the slow invariant manifold (SIM) is obtained. Also, the energy dissipation ratio of the NES and the percentage of the instantaneous total energy stored in the NES are calculated via the time-amplitude diagram. The results show that when the nonlinear effect decreases, the occurrence of energy pumping is less probable. Also, when the excitation amplitude decreases, the percentage of the instantaneous total energy stored in the NES increases as well as the amount of energy dissipation.

Nonlinear Energy Sink With Uncertain Parameters

2006 ◽  
Vol 1 (3) ◽  
pp. 187-195 ◽  
Author(s):  
E. Gourdon ◽  
C. H. Lamarque
Keyword(s):  
Normal Modes ◽  
Nonlinear Energy Sink ◽  
Nonlinear Normal Modes ◽  
Supplementary Information ◽  
Uncertain Parameters ◽  
Energy Pumping ◽  
Energy Sink ◽  
Nonlinear Normal ◽  
Polynomial Chaos Expansions ◽  
Nonlinear Energy

The effects of a nonlinear energy sink during the instationary regime are analyzed by introducing uncertain parameters to verify the robustness of the transient spatial energy transfer when parameters are not well known. It was shown that it is possible to passively absorb energy from a linear nonconservative system (damped) structure to a nonlinear attachment weakly coupled to the linear one. This rapid and irreversible transfer of energy, named energy pumping, is studied by taking into account uncertainties on parameters, especially damping (since damping plays a great role and there is a lack of knowledge about it). In essence, the nonlinear subsystem acts as a passive nonlinear energy sink for impulsively applied external vibrational disturbances. The aim is to be able to apply energy pumping in practice where the nonlinear attachment realization will never perfectly reflect the design. Since strong nonlinearities are involved, polynomial chaos expansions are used to obtain information about random displacements. Not only are numerical investigations done, but nonlinear normal modes and the role of damping are also analytically studied, which confirms the numerical studies and shows the supplementary information obtained compared to a parametrical study.

Targeted Energy Transfer With Several NES in Parallel: Theory and Experiments

2009 ◽  
Author(s):  
Alireza Ture Savadkoohi ◽  
Stephane Pernot ◽  
Claude Henri Lamarque
Keyword(s):  
Nonlinear Energy Sink ◽  
Single Degree Of Freedom ◽  
Strongly Nonlinear ◽  
Seismic Engineering ◽  
Energy Pumping ◽  
In Series ◽  
Energy Sink ◽  
Energy Activation ◽  
Nonlinear Energy ◽  
Theory And Experiments

The crucial point in the field of seismic engineering is to diminish the induced vibration energy as much as possible in a fast and almost irreversible manner. Recently the concept of Nonlinear Energy Sink (NES) has been developed such that the imposed energy to a linear single Degree of Freedom (DoF) substructure is transferred to one or series of strongly nonlinear light attachments; the mechanism is based on a 1:1 resonance capture. Nonlinear attachments can be designed to passively vibrate with any frequency; hence the system is efficient for both of transient and periodic excitations. Some drawbacks of these systems are as follows: they cannot kill the first peak of oscillation in the free time response that is linked to the energy activation of NES; moreover, the transformation of energy vanishes in time due to decrease of the strength of energy pumping. Using NES in series even cannot accelerate the phenomenon of energy pumping and some strange behavior due to the delay in the cooperation of NES in series is noticed. In this study, the transient dynamic behavior of multiple DoF systems with trees of parallel NES at each DoF is investigated, then experimental and numerical results of a four DoF structure with two parallel NES at the top floor are demonstrated and commented upon.

scholarly journals Analytical Analysis for Parameter Design of Attached Nonlinear Energy Sink

2021 ◽  
Vol 2021 ◽  
pp. 1-20
Author(s):  
Tianjiao Zhang ◽  
Luyu Li ◽  
Yilin Zheng
Keyword(s):  
Initial Conditions ◽  
Nonlinear Energy Sink ◽  
Excitation Amplitude ◽  
Harmonic Excitation ◽  
Dynamic Responses ◽  
Parameter Design ◽  
Target Energy ◽  
Energy Sink ◽  
Optimal Stiffness ◽  
Nonlinear Energy

The dynamic responses of a linear primary structure coupled with a nonlinear energy sink (NES) are investigated under harmonic excitation in the 1 : 1 resonance regime. In civil engineering, initial conditions are usually zero or approximately zero. Therefore, in this study, only these conditions are considered. The strongly modulated response (SMR), whose occurrence is conditional, is the precondition for effective target energy transfer (TET) in this system. Therefore, this study aims to determine the parameter range in which the SMR can occur. The platform phenomenon and other related phenomena are observed while analyzing slow-varying equations. An excitation amplitude interval during which the SMR can occur is obtained, and an approximate analytical solution of the optimal nonlinear stiffness is found. The numerical results show that the NES based on the optimal stiffness performs better in terms of control performance.

Thermal Effect on Dynamics of Beam with Variable-Stiffness Nonlinear Energy Sink

2020 ◽  
Vol 21 (1) ◽  
pp. 1-10 ◽  
Author(s):  
J. E. Chen ◽  
W. Zhang ◽  
M. H. Yao ◽  
J. Liu ◽  
M. Sun
Keyword(s):  
Variable Stiffness ◽  
Nonlinear Energy Sink ◽  
Excitation Amplitude ◽  
Harmonic Excitation ◽  
Absorption Efficiency ◽  
Nonlinear Stiffness ◽  
Vibration Absorption ◽  
Low Stiffness ◽  
Energy Sink ◽  
Nonlinear Energy

AbstractIn this study, we investigate the targeted energy transfer (TET) from a simply supported beam that is subjected to thermal variations and external excitations to a local nonlinear energy sink (NES). We derive the governing equation of motion for the beam with an NES device and study the influences of NES parameters on the vibration-suppressing effect. We obtain the optimized parameters of the NES under constant-amplitude harmonic excitation at room temperature. The optimized NES gradually loses its vibration absorption efficiency as the excitation amplitude and temperature increase. We change the nonlinear stiffness of the NES to mitigate the influence of temperature variation and show that NES efficiency can be enhanced by reducing the nonlinear stiffness. We propose a variable-stiffness NES, and the results demonstrate this NES is best for maintaining efficiency over the whole temperature range. We also analyze the transient responses of the system under impulse loads. Results indicate that, like the performance of the system subjected to harmonic excitation, an NES with relatively low stiffness can better suppress vibration with increasing impulse amplitude and temperature.

On an Active Control for a Structurally Nonlinear Mechanical System, Taking Into Account an Energy Pumping

2009 ◽  
Vol 4 (3) ◽  
Author(s):  
S. N. J. Costa ◽  
J. M. Balthazar
Keyword(s):  
Active Control ◽  
Impact Load ◽  
Nonlinear Energy Sink ◽  
Energy Pumping ◽  
Nonlinear Mechanical ◽  
Nonlinear Energy Pumping ◽  
Nonlinear Mechanical System ◽  
Optimal Linear ◽  
Energy Sink ◽  
Nonlinear Energy

The purpose of this work is to investigate the control of the oscillations and the suppression of vibrations in damped and coupled oscillators. In this sense, we look into the potential of using a nonlinear energy sink in combination with an optimal linear control for nonlinear system to suppress structure vibrations under an impact load. As a result, we obtain that the nonlinear energy pumping (a one-way passive and almost irreversible energy flow from a linear main system to a nonlinear attachment that acts as a nonlinear energy sink) can be enhanced with the help of appropriate active control. The numerical results show the effectiveness of the approach presented here.

Enhanced Targeted Energy Transfer by Vibro Impact Cubic Nonlinear Energy Sink

2018 ◽  
Vol 10 (06) ◽  
pp. 1850061 ◽  
Author(s):  
Y. M. Wei ◽  
X. J. Dong ◽  
P. F. Guo ◽  
Z. K. Peng ◽  
W. M. Zhang
Keyword(s):  
Energy Transfer ◽  
Energy Absorption ◽  
Nonlinear Energy Sink ◽  
Targeted Energy Transfer ◽  
Analytical Treatment ◽  
Efficient Manner ◽  
Energy Pumping ◽  
Energy Sink ◽  
Two Degree Of Freedom ◽  
Nonlinear Energy

Passive targeted energy transfer (TET) that describes a highly efficient manner of energy absorption is considerably enhanced by a new form of absorber proposed in this paper. The absorber is attached to the primary linear oscillator (LO) through cubic stiffness and bilateral barriers that set to induce vibro-impact (VI). Both essential nonlinearity and non-smooth nonlinearity are considered. Energy pumping phenomenon is found, and complexification averaging method is used to give an analytical treatment for the essential stiffness nonlinearity. At a low level of impulse excitation where energy pumping of nonlinear energy sink (NES) does not occur, by introducing VI energy pumping is brought up. At the optimal TET state, the vibro-impact cubic (VIC) absorber improves the efficiency of cubic NES on energy reduction to a certain degree. For a two-degree-of-freedom LO, the new absorber can absorb most energy of the broadband excitation which is a novel improvement compared with normal NES. Broadband excitations like input with sufficient bandwidth and random signals are found to be absorbed extensively by the VIC NES, meaning that the VIC NES as a nonlinear passive vibration absorber can be very efficient on broadband vibration energy absorption.

scholarly journals Dynamics of Nonlinear Primary Oscillator with Nonlinear Energy Sink under Harmonic Excitation: Effects of Nonlinear Stiffness

2018 ◽  
Vol 2018 ◽  
pp. 1-13 ◽  
Author(s):  
Min Sun ◽  
Jianen Chen
Keyword(s):  
Averaging Method ◽  
Nonlinear Energy Sink ◽  
Excitation Amplitude ◽  
Harmonic Excitation ◽  
Nonlinear Stiffness ◽  
Frequency Range ◽  
Steady State Responses ◽  
Energy Sink ◽  
State Responses ◽  
Nonlinear Energy

The dynamics of a system consisting of a nonlinear primary oscillator, subjected to a harmonic external force, and a nonlinear energy sink (NES) are investigated. The analytical solutions for the steady-state responses are obtained by the complexification-averaging method and the analytical model is confirmed by numerical simulations. The results indicate that the introduction of the NES can effectively suppress the vibrations of the primary oscillator. However, as the excitation amplitude increased, the NES may lose its efficiency within certain frequency range due to the appearance of the high response branches. Following the results analysis, it is concluded that this failure can be eliminated by reducing the nonlinear stiffness of the NES properly. The effects of nonlinear stiffness of the primary oscillator on the corresponding responses are also studied. The increase in this nonlinear stiffness can reduce the response amplitude and alter the frequency band where the high branches exist.

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