A Pendulum Type Particle Impact Damper

2021 ◽  
pp. 739-750
Author(s):  
Muhammad Ayaz Akbar ◽  
Wai On Wong
2008 ◽  
Vol 130 (2) ◽  
Author(s):  
Sanjiv Ramachandran ◽  
George Lesieutre

Particle impact dampers (PIDs) have been shown to be effective in vibration damping. However, our understanding of such dampers is still limited, based on the theoretical models existing today. Predicting the performance of the PID is an important problem, which needs to be investigated more thoroughly. This research seeks to understand the dynamics of a PID as well as those parameters which govern its behavior. The system investigated is a particle impact damper with a ceiling, under the influence of gravity. The base is harmonically excited in the vertical direction. A two-dimensional discrete map is obtained, wherein the variables at one impact uniquely dictate the variables at the next impact. This map is solved using a numerical continuation procedure. Periodic impact motions and “irregular” motions are observed. The effects of various parameters such as the gap clearance, coefficient of restitution, and the base acceleration are analyzed. The dependence of the effective damping loss factor on these parameters is also studied. The loss factor results indicate peak damping for certain combinations of parameters. These combinations of parameters correspond to a region in parameter space where two-impacts-per-cycle motions are observed over a wide range of nondimensional base accelerations. The value of the nondimensional acceleration at which the onset of two-impacts-per-cycle solutions occurs depends on the nondimensional gap clearance and the coefficient of restitution. The range of nondimensional gap clearances over which two-impacts-per-cycle solutions are observed increases as the coefficient of restitution increases. In the regime of two-impacts-per-cycle solutions, the value of nondimensional base acceleration corresponding to onset of these solutions initially decreases and then increases with increasing nondimensional gap clearance. As the two-impacts-per-cycle solutions are associated with high loss factors that are relatively insensitive to changing conditions, they are of great interest to the designer.


2010 ◽  
Vol 52 (7) ◽  
pp. 1015-1022 ◽  
Author(s):  
Yanchen Du ◽  
Shulin Wang

Author(s):  
Moez Trigui ◽  
Emmanuel Foltete ◽  
Noureddine Bouhaddi

In this paper, an experimental characterisation of a particle impact damper (PID) under periodic excitation is investigated. The developed method allows the measurement of damping properties of PID without the supplementary use of a primary structure. The passive damping of PID varies with the excitation frequency and its design parameters. The nonlinear damping of PID is then interpreted as an equivalent viscous damping to be introduced in a finite element model of a structure to predict its dynamic response. The results of numerical simulations are in good agreement with those of experiment and show the relevance of the developed method to predict the dynamic behaviour of a structure treated by PID’s.


Author(s):  
Riadh Chaari ◽  
Fathi Djemal ◽  
Fakher Chaari ◽  
Mohamed Slim Abbes ◽  
Mohamed Haddar

Impact dampers are efficient in many industrial applications with a wide range of frequencies. An experimental analysis of the impact damping of spherical balls is investigated to simplify the particle impact damping design and improve the vibration suppression. The objective of the study is to analyze some of the design parameters of impact damper using spherical balls. The experimental investigation consists to test the effect of the ball size for each mass level, the number of balls for each size level and different exciting force levels on vibrations of the main structure. The parametric study provided useful information to understand and optimize Particle Impact Damping design.


2020 ◽  
Vol 169 ◽  
pp. 107487
Author(s):  
Jie Jin ◽  
Wonseok Yang ◽  
Hyo-In Koh ◽  
Junhong Park

Author(s):  
Hamid R. Hamidzadeh

The particle impact damper is an effective vibration damping treatment that can be used in the cases where visco-elastic constrained layer damping fails due to excessive surrounding temperature. In this type of passive damping, particles move in a container attached to the vibrating system resulting in plastic impact with the container. In the presented theoretical study, the damping characteristics of free oscillation for a vertical system with an initial displacement are considered and a governing equation for the system under free vibration with a particle damper is derived. To evaluate the damping characteristics for the free vibrating system, the equivalent damping ratio is determined by considering both kinematics and kinetics of the particle motion and its impacts with the container. The presented solution concludes that in general damping effectiveness can be enhanced by increasing the mass of the particle in comparison with total mass of the system. Mathematical optimum clearance for the moving particle and the equivalent viscous damping ratio are determined for the best performance of the particle impact damper.


2008 ◽  
Vol 2008 ◽  
pp. 1-6 ◽  
Author(s):  
Yanchen Du ◽  
Shulin Wang ◽  
Yan Zhu ◽  
Laiqiang Li ◽  
Guangqiang Han

The energy dissipation mechanisms of conventional impact damper (CID) are mainly momentum exchange and friction. During the impact process, a lot of vibration energy cannot be exhausted but reverberated among the vibration partners. Besides, the CID may produce the additional vibration to the system or even amplify the response in the low-frequency vibration. To overcome these shortcomings, this paper proposes a new fine particle impact damper (FPID) which for the first time introduces the fine particle plastic deformation as an irreversible energy sink. Then, the experiments of the cantilevered beam with the CID and that with the FPID are, respectively, carried out to investigate the behavior of FPID. The experimental results indicate that the FPID has a better performance in vibration damping than in the CID and the FPID works well in control of the vibration with frequency lower than 50 Hz, which is absent to the non-obstructive particle damper. Thus, the FPID has a bright and significant application future because most of the mechanical vibration falls in the range of low freqency.


Sign in / Sign up

Export Citation Format

Share Document