A Circular Eccentric Vibration Absorber with Circumferentially Graded Acoustic Black Hole Features

2022 ◽  
pp. 1-35
Author(s):  
Hongli Ji ◽  
Xiaoning Zhao ◽  
Ning Wang ◽  
Wei Huang ◽  
Jinhao Qiu ◽  
...  
Keyword(s):  
Black Hole ◽  
Vibration Suppression ◽  
Coupling Model ◽  
Structural Vibration ◽  
Vibration Absorber ◽  
Dynamic Vibration Absorber ◽  
Modal Damping ◽  
Host Structure ◽  
Gradient Variation ◽  
Structural Vibration Suppression

Abstract A previously proposed planar axisymmetric dynamic vibration absorber (DVA), with embedded acoustic black hole (ABH) features, has been shown to suffer from the very selective coupling with the host structure, thus compromising its vibration reduction performance. To tackle the problem, an eccentric ABH-based circular DVA whose thickness profile is tailored according to a circumferential gradient variation is proposed in this paper. This new configuration preserves the ABH profile in the radial direction alongside a continuous variation along the circumferential direction and breaks the axisymmetry of the original DVA design at the same time. While the former permits the ABH features to fully play out in a continuous manner, the later entails a more effective coupling with the host structure. These salient properties have been demonstrated and confirmed both numerically and experimentally by examining a benchmark plate structure. For analyses, a coupling model embracing the host structure and the add-on DVAs is established which allows the calculation of the coupling coefficient, a vital quantity to guide the DVA design. Studies demonstrate the advantages of the proposed DVA over existing designs for the same given mass. The enriched structural coupling and the enhanced modal damping, arising from the eccentric and circumferentially graded ABH design, are shown to be the origin of such improvement. All in all, the physical process underpinning the dynamic absorber principle and waveguide absorber from the host structures is simultaneously consolidated, thus leading to superior broadband structural vibration suppression.

Energy Harvesting Dynamic Vibration Absorbers

2013 ◽  
Vol 80 (4) ◽  
Author(s):  
Shaikh Faruque Ali ◽  
Sondipon Adhikari
Keyword(s):  
Energy Harvesting ◽  
Vibration Suppression ◽  
Fixed Point Theory ◽  
Electrical Circuit ◽  
Closed Form Expression ◽  
Vibration Absorber ◽  
Original Structure ◽  
Dynamic Vibration Absorber ◽  
Dynamic Vibration ◽  
Host Structure

Energy harvesting is a promise to harvest unwanted vibrations from a host structure. Similarly, a dynamic vibration absorber is proved to be a very simple and effective vibration suppression device, with many practical implementations in civil and mechanical engineering. This paper analyzes the prospect of using a vibration absorber for possible energy harvesting. To achieve this goal, a vibration absorber is supplemented with a piezoelectric stack for both vibration confinement and energy harvesting. It is assumed that the original structure is sensitive to vibrations and that the absorber is the element where the vibration energy is confined, which in turn is harvested by means of a piezoelectric stack. The primary goal is to control the vibration of the host structure and the secondary goal is to harvest energy out of the dynamic vibration absorber at the same time. Approximate fixed-point theory is used to find a closed form expression for optimal frequency ratio of the vibration absorber. The changes in the optimal parameters of the vibration absorber due to the addition of the energy harvesting electrical circuit are derived. It is shown that with a proper choice of harvester parameters a broadband energy harvesting can be obtained combined with vibration reduction in the primary structure.

Passive Damping Augmentation Using Macro-Fiber Composite Actuators

2002 ◽  
Author(s):  
Kazuhiko Adachi ◽  
Gyuhae Park ◽  
Daniel J. Inman
Keyword(s):  
Vibration Suppression ◽  
Fiber Composite ◽  
Structural Vibration ◽  
Vibration Absorber ◽  
Single Degree Of Freedom ◽  
Cantilevered Beam ◽  
Macro Fiber Composite ◽  
Resonant Shunt ◽  
Structural Vibration Suppression ◽  
Shunt Circuit

This paper aims at presenting the structural vibration-suppression capability of the recently developed Macro-Fiber Composite (MFC) actuator as a passive piezoelectric absorber using an inductive resonant shunt circuit. The resistance and inductance of the series RL shunt circuit are designed by the analogy with the single-degree-of-freedom mechanical damped vibration absorber and by using the maximum power transfer theorem of the electric network. Experimental test of a simple cantilevered beam demonstrates that the MFC actuator has excellent capability of improving the dynamic response of the beam as a piezoelectric damping system. The damping enhancement performance of the MFC actuator is superior to that of the conventional monolithic PZT actuator.

Piezoelectric Structural Vibration Control Using Active Resonator Absorber

2001 ◽  
Author(s):  
David W. Knowles ◽  
Nader Jalili ◽  
Sriram Ramadurai
Keyword(s):  
Vibration Suppression ◽  
Resonance Condition ◽  
Piezoelectric Materials ◽  
Structural Vibration ◽  
Vibration Absorber ◽  
Practical Implementation ◽  
Primary System ◽  
Dynamic Feedback ◽  
Dynamic Vibration Absorber ◽  
Active Resonator

Abstract A novel dynamic vibration absorber is presented while exploring its practical implementation using piezoelectric ceramic (PZT) inertial actuators. It is referred to as active resonator absorber (ARA). The ARA is a passive absorber with an additional dynamic feedback compensator within the PZT actuator. Without any controller, the PZT inertial actuator becomes a passive vibration absorber due to the internal damping and stiffness properties of piezoelectric materials. Hence, it is inherently fail-safe. For active operation, the compensator parameters are designed such that a resonance condition is intentionally created within the absorber to mimic the vibratory energy from the system of concern to which it is attached. The resonance condition can be created through the appropriate design of the compensator and implemented through adjusting the external electrical voltage applied to the absorber. Because the parameters of the PZT actuators (i.e. stiffness, damping, and effective mass) are estimates, compensator designs based on these parameters would result in partial vibration suppression, when utilized in real applications. An auto-tuning method is, therefore, introduced to effectively tune the compensator parameters to improve vibration suppression quality. The effectiveness and stability of the proposed absorber is demonstrated through simulations when appended on a SDOF primary system.

scholarly journals Vibration suppression of structures using tuned mass damper technology: A state-of-the-art review

2021 ◽  
pp. 107754632098430
Author(s):  
Fan Yang ◽  
Ramin Sedaghati ◽  
Ebrahim Esmailzadeh
Keyword(s):  
Mathematical Modeling ◽  
Vibration Suppression ◽  
State Of The Art ◽  
Optimization Procedure ◽  
Tuned Mass Damper ◽  
Structural Vibration ◽  
Practical Realization ◽  
Reliable Operation ◽  
Mass Damper ◽  
Structural Vibration Suppression

To date, considerable attention has been paid to the development of structural vibration suppression techniques. Among all vibration suppression devices and techniques, the tuned mass damper is one of the most promising technologies due to its mechanical simplicity, cost-effectiveness, and reliable operation. In this article, a critical review of the structural vibration suppression using tuned mass damper technology will be presented mainly focused on the following four categories: (1) tuned mass damper technology and its modifications, (2) tuned mass damper technology in discrete and continuous structures (mathematical modeling), (3) optimization procedure to obtain the optimally designed tuned mass damper system, and (4) active tuned mass damper and semi-active tuned mass damper with the practical realization of the tuned mass damper technologies.

Adaptive-passive structural vibration attenuation using distributed absorbers

2002 ◽  
Vol 216 (3) ◽  
pp. 223-235 ◽  
Author(s):  
N Jalili ◽  
E Esmailzadeh
Keyword(s):  
Vibration Suppression ◽  
Sufficient Conditions ◽  
Structural Vibration ◽  
Dynamic Vibration Absorber ◽  
Vibration Attenuation ◽  
Adaptive Capability ◽  
On Line ◽  
Lumped Masses ◽  
Necessary And Sufficient ◽  
Tuning Strategy

A distributed dynamic vibration absorber with adaptive capability is presented to improve vibration suppression characteristics of harmonically excited structures. A double-ended cantilever beam carrying intermediate lumped masses forms the absorber subsection. The adaptive capability is achieved through concurrent adjustment of the positions of the moving masses, along the beam, to comply with the desired optimal performance. The necessary and sufficient conditions for the existence of periodic oscillatory behaviour, along with some physical bounds placed on the absorber parameters, form a constrained optimization problem for the optimum tuning strategy. Through numerical simulations it is shown that adaptive tuning is achieved by the variation of tuning mass locations such that the first-mode natural frequency is modulated on-line. The optimally tuned absorber provides considerable vibration suppression improvement over the passive and detuned absorbers.

Numerical and Experimental Studies of Pendulum Dynamic Vibration Absorber for Structural Vibration

2020 ◽  
Vol 143 (1) ◽  
Author(s):  
Seon Il Ha ◽  
Gil Ho Yoon
Keyword(s):  
Experimental Studies ◽  
Point Of View ◽  
Structural Vibration ◽  
Vibration Absorber ◽  
Square Root ◽  
Vibration Absorbers ◽  
Structural Vibrations ◽  
Dynamic Vibration Absorber ◽  
Dynamic Vibration ◽  
Resonance Frequencies

Abstract This research presents a pendulum dynamic vibration absorber (PDVA) consisting of a spring and a mass in order to attenuate structural vibrations at two frequencies of hosting structure. It is a convention to attach several dynamic absorbers to hosting structure for the sake of the attenuations of structural vibrations at multiple frequencies with enlarged bandwidth and often it increases the total mass and the installation cost. Therefore, the reduction of the number of vibration absorbers for multiple excitation frequencies is an important issue from an engineering point of view. To resolve these difficulties, this study proposes to adopt the vibration absorber framework of the spring-mass vibration as well as the pendulum vibration simultaneously with the present PDVA system. It is composed of a spring and a mass but being allowed to swing circumferentially, the structural vibrations at the two resonance frequencies, i.e., the square root of stiffness over mass and the square root of a length over gravidity, can be simultaneously attenuated. As the length of the spring of the present PDVA is varied, the effective ranges for the pendulum dynamic vibration absorber become widen. To prove the concept of the present PDVA, this research conducts several numerical simulations and experiments.

Sign in / Sign up

Export Citation Format

Share Document