Improvement of the Vibration Damping Performance for Parallel Wire Type Positioning Systems (Technique with Natural Frequency Control and Tuned Mass Damper)

The submitted paper is focused on the design of Tuned Mass Damper in order to reduce excessive level of vibration. This device is designed to be active at the first natural frequency of the structure. Subsequently, the efficiency of the new dynamic system (structure-TMD) is verified for several types of time-dependent loads, which express swaying vandal, jumping vandal and moving pedestrian.

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Mitigation of Vortex-Induced Vibrations of a Pivoted Circular Cylinder Using an Adaptive Pendulum Tuned-Mass Damper

Journal of Fluids Engineering ◽

10.1115/1.4025059 ◽

2013 ◽

Vol 135 (11) ◽

Cited By ~ 1

Author(s):

Sina Kheirkhah ◽

Richard Lourenco ◽

Serhiy Yarusevych ◽

Sriram Narasimhan

Keyword(s):

Frequency Response ◽

Natural Frequency ◽

Damping Ratio ◽

Tuned Mass Damper ◽

Single Frequency ◽

Fundamental Frequencies ◽

Transverse Vibrations ◽

Synchronization Region ◽

Vortex Induced Vibrations ◽

Mass Damper

A novel adaptive pendulum tuned-mass damper (TMD) was integrated with a two degree-of-freedom (DOF) cylindrical structure in order to control vortex-induced vibrations of the structure. The natural frequency of the TMD was adjusted autonomously in order to control the vortex-induced vibrations. The experiments were performed at a constant Reynolds number of 2100 and for four reduced velocities, 4.18, 5.44, 6.00, and 6.48. Two TMD damping ratios, 0 and 0.24, were investigated for a constant TMD mass ratio of 0.087. The results demonstrate that tuning the natural frequency of the TMD to the natural frequency of the structure decreases the amplitudes of transverse and streamwise vibrations of the structure significantly. Specifically, the transverse amplitudes of vibrations are decreased by a factor of ten and streamwise amplitudes of vibrations are decreased by a factor of three. Depending on the value of the TMD damping ratio, the frequency of transverse vibrations is either characterized by the natural frequency of the structure or by two other fundamental frequencies, one higher and the other lower than the natural frequency of the structure. The results demonstrate that, independent of the TMD damping and tuning frequency ratios, the frequency of streamwise vibrations matches that of the transverse vibrations in the synchronization region, and the cylinder traces elliptic trajectories. A mathematical model is proposed to gain insight into the frequency response of the structure and fluid-structure interactions. The model shows that, for low TMD damping ratios, the frequency response of the structure equipped with the TMD is characterized by two fundamental frequencies; whereas, for relatively high TMD damping ratios, the frequency response of the structure is characterized by a single frequency, i.e., the natural frequency. In both cases, the fluid forcing within the synchronization region is linked to the fundamental frequency/frequencies of the structure. Thus, the classical definition of synchronization applies to multiple DOF structures undergoing vortex-induced vibrations.

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Dynamic analysis of viscoelastic tuned mass damper system under harmonic excitation

Journal of Vibration and Control ◽

10.1177/1077546319833887 ◽

2019 ◽

Vol 25 (11) ◽

pp. 1768-1779 ◽

Cited By ~ 6

Author(s):

Jun Dai ◽

Zhao-Dong Xu ◽

Pan-Pan Gai

Keyword(s):

Frequency Dependence ◽

Natural Frequency ◽

Storage Modulus ◽

Primary Structure ◽

Loss Factor ◽

Design Strategy ◽

Tuned Mass Damper ◽

Optimum Frequency ◽

Mass Damper ◽

And Control

The purpose of this paper is to investigate the contribution of viscoelastic material (VEM) to the control performance of the viscoelastic tuned mass damper (VTMD). Firstly, the equivalent fractional derivation Kelvin model is used to describe the frequency dependence of viscoelasticity in VTMD, and an index is proposed to characterize the level of frequency dependence. Then the effects of the high loss factor of VEM and frequency dependence of viscoelasticity on the effectiveness and robustness of VTMD control are analyzed by numerical examples. At last, a design strategy for VTMD is proposed to select the type of VEM and optimize its stiffness contribution. The results show that the frequency dependence of shear storage modulus of VEM is beneficial to further reduce the dynamic response of the primary structure equipped with VTMD, and the loss factor of VEM determines the optimum frequency ratio and control effect of VTMD. Compared to the conventional tuned mass damper, VTMD has a better robustness for the positive error of the natural frequency of VTMD but has a worse robustness for the negative error. The frequency dependence of shear storage modulus of VEM is beneficial to the robustness of VTMD for both the positive and negative errors of the natural frequency of the primary structure. The VEM with a strong frequency dependence of shear storage modulus is the ideal VEM for VTMD, and the proposed design strategy can deal with the trade-off between the control effectiveness and control robustness of VTMD.

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Vibration Control Performance of Damping Coupled Tuned Mass Dampers

Seismic Engineering, Volume 1 ◽

10.1115/pvp2004-2940 ◽

2004 ◽

Author(s):

Nobuo Masaki ◽

Hisashi Hirata

Keyword(s):

Vibration Control ◽

Natural Frequency ◽

Tuned Mass Damper ◽

Control Performance ◽

Tuned Mass Dampers ◽

Mass Unit ◽

Optimal Value ◽

Mass Damper ◽

Rubber Bearings ◽

Prefabricated Houses

Recently tuned mass dampers have been installed on three-story prefabricated houses for reducing of traffic-induced vibration and improving living comfort. This tuned mass damper consists of a mass unit, spring units and laminated rubber bearings. The mass is supported by four laminated rubber bearings, and spring units are used for adjusting the natural frequency of the tuned mass damper to the optimal value. Vibration control performance of this type of tuned mass dampers is deteriorated when the natural frequency of the house is changed. To solve this problem, the authors have developed a damping coupled tuned mass damper. In this type of tuned mass damper, two mass units having slightly different natural frequencies are coupled by using a damping unit. In this paper, mechanism and vibration control performance of the damping coupled tuned mass damper are described.

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Numerical and Experimental Study on Dynamic Response Mitigation of Tension Leg Platform Using Tuned Mass Damper

Journal of Ship Research ◽

10.5957/josr.06200039 ◽

2021 ◽

pp. 1-12

Author(s):

Mohammad Reza Tabeshpour ◽

Latif Nikmehr

Keyword(s):

Natural Frequency ◽

Experimental Studies ◽

Tuned Mass Damper ◽

Offshore Structures ◽

Response Amplitude ◽

Structural Safety ◽

Wave Load ◽

Tension Leg Platform ◽

Stable Conditions ◽

Mass Damper

Response amplitude mitigation of the offshore structures like tension leg platform (TLP) is important since these structures are always exposed to environmental loads such as waves, and in the case of TLP, reduction in response amplitude of platform causes reduction in stress range in tendons; this would increase the fatigue life of tendons, and therefore, increases the structural safety. Also providing stable conditions for machinery and crew increases the efficiency and functionality of the platform. This article thus aims to investigate the possibility and effectiveness of applying tuned mass damper (TMD) as a passive structural control system to suppress the surge motion of TLP that is exposed to wave load. Both numerical and experimental studies were carried out to assess the performance of the TMD. A close agreement is obtained between the numerical simulations and experimental results. The results of numerical and experimental investigations in this study indicate that applying the TMD, tuned to the surge natural frequency of the platform or frequencies close to the surge natural frequency of the platform, doesn’t have efficiency in reducing the surge responses of TLP in the range of probable waves in seas and oceans.

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Tuned mass damper and high static low dynamic stiffness isolator for vibration reduction of beam structure

Proceedings of the Institution of Mechanical Engineers Part K Journal of Multi-body Dynamics ◽

10.1177/1464419319876390 ◽

2019 ◽

Vol 234 (1) ◽

pp. 95-115 ◽

Cited By ~ 1

Author(s):

Meysam Raei ◽

Morteza Dardel

Keyword(s):

Natural Frequency ◽

Dynamic Stiffness ◽

Excitation Amplitude ◽

Tuned Mass Damper ◽

Degree Of Freedom ◽

Negative Stiffness ◽

Low Frequencies ◽

First Case ◽

Mass Damper ◽

Two Degree Of Freedom

In this work, the combination effect of tuned mass damper and high static low dynamic stiffness (HSLDS) isolator is investigated in reducing the vibration amplitude of Euler–Bernoulli beam with a nonlinear attachment. The performance of the absorber is studied in two cases; the first case, HSLDS isolator is one degree of freedom and the second case, two degree of freedom isolator is combined of HSLDS isolator and tuned mass damper absorber. By comparing the performance of these two isolators, it is revealed the two degree of freedom isolator has much better performance in direct force excitation and also improves the system performance in the base excitation. This isolator reduces the system amplitude at all frequencies, especially ultra-low frequencies, which is the main advantage to this isolator with respect to other isolators and reduces the natural frequency until the phenomenon of resonance occurs at a lower frequency. Moreover, decreasing the natural frequency increases the damping and in quasi zero stiffness and negative stiffness structure, the system has supercritical damping. This isolator is studied for positive, quasi zero and negative stiffness. The results show that the system with quasi zero stiffness has the best performances. Also, by increasing the excitation amplitude, the isolator loses its effectiveness.

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Maximizing Damping Effect of the Vibration by Changing the Natural Frequency of Tuned Mass Damper

Korean Science Education Society for the Gifted ◽

10.29306/jseg.2019.11.1.26 ◽

2019 ◽

Vol 11 (1) ◽

pp. 26-36

Author(s):

Seongmin Hong ◽

Bumjin Kim ◽

Eun-Jeong Yu

Keyword(s):

Natural Frequency ◽

Tuned Mass Damper ◽

Damping Effect ◽

Mass Damper

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Electromechanical semi-passive nonlinear tuned mass damper for efficient vibration damping

Journal of Sound and Vibration ◽

10.1016/j.jsv.2013.06.006 ◽

2013 ◽

Vol 332 (22) ◽

pp. 5696-5709 ◽

Cited By ~ 14

Author(s):

Mickaël Lallart ◽

Linjuan Yan ◽

Yi-Chieh Wu ◽

Daniel Guyomar

Keyword(s):

Tuned Mass Damper ◽

Vibration Damping ◽

Mass Damper ◽

Nonlinear Tuned Mass Damper

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Series-Type Pendulum Tuned Mass Damper-Tuned Sloshing Damper

Journal of Vibration and Acoustics ◽

10.1115/1.4044866 ◽

2019 ◽

Vol 142 (1) ◽

Cited By ~ 2

Author(s):

J. S. Love ◽

K. P. McNamara ◽

M. J. Tait ◽

T. C. Haskett

Keyword(s):

Natural Frequency ◽

Analytical Study ◽

Linear Structure ◽

Cost Effective ◽

Tuned Mass Damper ◽

Restoring Force ◽

Equivalent Mechanical Model ◽

Mass Damper ◽

Series Type ◽

Structural Motion

Abstract A pendulum-type tuned mass damper (TMD)-tuned sloshing damper (TSD) system is proposed as a cost-effective device to reduce wind-induced structural motion. Lagrange's principle is employed to develop an equivalent mechanical model for the system. The sloshing liquid provides additional gravitational restoring force to the pendulum TMD but does not provide a corresponding increase to its inertia. As a result, the natural frequency of the pendulum TMD is increased due to the TSD degree-of-freedom. Shake table testing is conducted on several pendulum TMD-TSD systems that are subjected to harmonic base excitation at discrete frequencies near the natural frequency of the pendulum TMD. The modeled and experimental results are in reasonable agreement when the liquid is not shallow or the response amplitude is not large. The pendulum TMD-TSD is coupled to a linear structure, and it is demonstrated through an analytical study that the device provides performance that is comparable to a traditional TMD. The proposed system is advantageous because it does not require a viscous damping system that is often one of the most costly components of traditional TMDs.

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Controlling the Limit-Cycle of the Ziegler Column via a Tuned Piezoelectric Damper

Mathematical Problems in Engineering ◽

10.1155/2015/942859 ◽

2015 ◽

Vol 2015 ◽

pp. 1-9 ◽

Cited By ~ 4

Author(s):

Francesco D’Annibale ◽

Giuseppe Rosi ◽

Angelo Luongo

Keyword(s):

Numerical Simulations ◽

Nonlinear Analysis ◽

Mechanical System ◽

Natural Frequency ◽

Limit Cycles ◽

Control Strategy ◽

Tuned Mass Damper ◽

Stability Domain ◽

Electrical Characteristics ◽

Mass Damper

This paper is about the nonlinear analysis of a piezoelectric controlled Ziegler column. The piezoelectric controller, here referred to as Tuned Piezoelectric Damper (TPD), possesses evanescent characteristics and, moreover, it is tuned to the first natural frequency of the mechanical system, thus resembling the well-known Tuned Mass Damper. This means that the flow of energy between mechanical and electrical subsystems is driven by the resonance (Den Hartog principle) and magnified by the singularity of the evanescent electrical characteristics. Numerical simulations, showing how the proposed control strategy is effective in increasing the linear stability domain and decreasing the amplitude of the limit-cycles in the postcritical range, are presented.

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