Global dynamics and performance of vibration reduction for a new vibro-impact bistable nonlinear energy sink

A nonlinear energy sink (NES) approach is proposed for whole-spacecraft vibration reduction. Frequency sweeping tests are conducted on a scaled whole-spacecraft structure without or with a NES attached. The experimental transmissibility results demonstrate the significant reduction of the whole-spacecraft structure vibration over a broad spectrum of excitation frequency. The NES attachment hardly changes the natural frequencies of the structure. A finite element model is developed, and the model is verified by the experimental results. A two degrees-of-freedom (DOF) equivalent model of the scaled whole-spacecraft is proposed with the two same natural frequencies as those obtained via the finite element model. The experiment, the finite element model, and the equivalent model predict the same trends that the NES vibration reduction performance becomes better for the increasing NES mass, the increasing NES viscous damping, and the decreasing nonlinear stiffness. The energy absorption measure and the energy transition measure calculated based on the equivalent model reveals that an appropriately designed NES can efficiently absorb and dissipate broadband-frequency energy via nonlinear beats, irreversible targeted energy transfer (TET), or both for different parameters.

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Design and performance analysis of a nonlinear energy sink attached to a beam with different support conditions

Proceedings of the Institution of Mechanical Engineers Part C Journal of Mechanical Engineering Science ◽

10.1177/0954406215578705 ◽

2015 ◽

Vol 230 (4) ◽

pp. 527-542 ◽

Cited By ~ 10

Author(s):

Majid Kani ◽

Siamak E Khadem ◽

Mohammad H Pashaei ◽

Morteza Dardel

Keyword(s):

Particle Swarm Optimization ◽

Performance Analysis ◽

Nonlinear Energy Sink ◽

Optimization Method ◽

Primary System ◽

Swarm Optimization ◽

Energy Sink ◽

Support Conditions ◽

And Performance ◽

Nonlinear Energy

In this work, design and performance analysis of a nonlinear energy sink, attached to a beam (the primary system) with different support conditions, will be investigated. Here, the effects of both beam properties and external shock excitation are studied. For this purpose, equations of motion are derived by the Lagrange method. Then, parameters of the nonlinear energy sink are optimized by both sensitivity analysis and particle swarm optimization method. The results show that, increasing the first natural frequency of the primary system, on which an external impulse is imposed, will postpone the nonlinear energy sink activation. Also, increasing the amplitude of the shock excitation will tend to decrease the optimum value of the nonlinear energy sink stiffness. Using the particle swarm optimization method to obtain the optimized parameters of the nonlinear energy sink and its interaction with the primary system, which is a continuous one, is a new research area presented in this work.

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Global Dynamics and Optimal Design of a New Highly Efficient Nonlinear Energy Sink Based on Magnetic-Elastic Impacts with Negative Stiffness

10.21203/rs.3.rs-698793/v1 ◽

2021 ◽

Author(s):

Shuangbao Li ◽

Tingting Wang ◽

Jianen Chen

Keyword(s):

Energy Dissipation ◽

Optimal Design ◽

Nonlinear Energy Sink ◽

Negative Stiffness ◽

Global Dynamics ◽

Elastic Impact ◽

Highly Efficient ◽

Dissipation Rates ◽

Energy Sink ◽

Nonlinear Energy

Abstract A new highly efficient elastic-impact bistable nonlinear energy sink (EI-BNES) based on magnetic-elastic impacts with negative stiffness and bistability is proposed and optimized through global dynamical analysis. The EI-BNES has better robustness and higher energy dissipation rates with nearly more than 96.5\% for broadband impulsive excitations than the traditional cubic NESs and single bistable NESs. The structure of negative stiffness impacts is realized by reasonable layout of permanent ring magnets and springs. A two-degree-of-freedom (two-DOF) elastic-impact system is established to describe the coupled nonlinear interaction between the main structure and the attached EI-BNES. A global Melnikov reduction analysis (GMRA) is proposed to study global dynamics and homoclinic bifurcations of the reduced two-dimensional subsystem, which is used to explain the mechanism of nonlinear targeted energy transfer (TET) and detect the threshold of impulsive amplitudes of EI-BNES for in-well and compound motions between in-well and cross-well resonance responses. A special type of saddle-center equilibrium points is also found in the non-smooth system of the EI-BNES and can be used to effectively increase the energy dissipation rates. The optimal design criterion of the tuned EI-BNES for better dissipation performance is also first discussed based on the GMRA and numerical techniques for calculating the Melnikov function of the non-smooth systems. The effectiveness of the analytical GMRA is also verified by numerical simulations.

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Vibration Suppression for Beam-Like Repeating Lattice Structure Based on Equivalent Model by a Nonlinear Energy Sink

Mathematical Problems in Engineering ◽

10.1155/2021/6659598 ◽

2021 ◽

Vol 2021 ◽

pp. 1-15

Author(s):

Gen Liu ◽

Gongfa Chen ◽

Fangsen Cui

Keyword(s):

Vibration Suppression ◽

Lattice Structure ◽

Vibration Reduction ◽

Coupled System ◽

Nonlinear Energy Sink ◽

Equivalent Model ◽

External Excitation ◽

Suppression Effect ◽

Energy Sink ◽

Nonlinear Energy

Based on the fully deployed space beam-like truss, the vibration reduction of the lattice structure is studied by using the local NES (nonlinear energy sink) attachment in this paper. The beam-like lattice structure is modeled as an equivalent linear continuous system (a finite length beam) by the equivalent method and validated with the finite element results. The dynamic vibration equations for the equivalent cantilever beam are established and the governing equations for the equivalent beam with NES are approximated by the Galerkin method. The displacement responses of the beam with and without NES attached under shock excitation are obtained. With NES at different positions, the amplitude responses of the coupled system under the external excitation at different positions are calculated to evaluate the suppression effect of the NES attachment to the structure. And with different masses of the NES, the amplitude responses of the coupled structure subject to the external excitation at different positions are also investigated to get the influence of the mass of the NES attachment to the vibration reduction. It can be seen from the results that the NES attachment can attenuate the response of the beam-like truss under transient excitation efficiently. And with the mass of NES attachment increasing, the vibration amplitude of the coupled system declines more rapidly, and the energy consumption efficiency of the NES attachment is higher. Moreover, the attenuation effect of the NES with different masses is experimentally analyzed. The experimental results are in good accord with the theoretical calculation.

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Application of the Nonlinear Energy Sink Systems in Vibration Suppression of Railway Bridges

ASME 2010 10th Biennial Conference on Engineering Systems Design and Analysis, Volume 5 ◽

10.1115/esda2010-24629 ◽

2010 ◽

Cited By ~ 2

Author(s):

Davood Younesian ◽

Amir Nankali ◽

M. Emad Motieyan

Keyword(s):

Passive Control ◽

Vibration Suppression ◽

Nonlinear Energy Sink ◽

Solution Technique ◽

Moving Loads ◽

Railway Bridges ◽

Energy Sink ◽

And Performance ◽

Euler Bernoulli Beam ◽

Nonlinear Energy

Vibration suppression of railway bridges using nonlinear energy sink systems (NES) is studied in this paper. Train is modeled as a set of successive moving loads traveling on an Euler-Bernoulli beam. Energy sink as a new passive control strategy is employed as the suppression system. Galerkin method here is adopted as the solution technique. Within a parametric study, series of numerical simulations are carried out and performance of the passive control system is investigated. It is numerically found that an appropriately designed NES can passively reduce the displacement of the bridge up to 43%.

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