scholarly journals Optimization and analysis of a grounded type dynamic vibration absorber with lever component

2020 ◽  
Vol 103 (4) ◽  
pp. 003685042095988
Author(s):  
Yongjun Shen ◽  
Zikang Xing ◽  
Shaopu Yang ◽  
Xianghong Li
Keyword(s):  
Effective Mass ◽  
Vibration Absorber ◽  
Engineering Practice ◽  
Control Performance ◽  
Mass Ratio ◽  
Dynamic Vibration Absorber ◽  
Amplification Ratio ◽  
Dynamic Vibration ◽  
Optimum Parameters ◽  
Auxiliary Mass

Dynamic vibration absorber (DVA) with large auxiliary mass has better control performance, but it is also more bulky. Therefore, the mass ratio (the ratio of auxiliary mass of DVA to mass of controlled object) is usually limited to make the DVA easy to install and suitable for engineering practice. In this paper a grounded type DVA with lever component is proposed, which aims to increase the effective mass and reduce unnecessary mass to improve control performance of the DVA. Firstly, the motion differential equations of the DVA are established and solved. Secondly, the optimum parameters are obtained based on H∞ and H2 optimization criterion. Then, the performances of the grounded type DVA equipped with and without the lever are investigated. Finally, the control performance of the DVA is compared with other three typical DVAs under H∞ and H2 criterion. In this type DVA there are no global optimum parameters, and larger frequency ratio will get better control performance. If the amplification ratio (the ratio of lever power arm to lever resistance arm) is greater than 1, the introduced lever will contribute to control performance of the DVA. Its control performance is better than those of other three typical DVAs. The use of the lever can increase the effective mass of the DVA, thereby improving the control performance of the DVA. The DVA can achieve good performance at small mass ratio by adjusting amplification ratio, which may provide theoretical basis for the design of new kinds of DVAs.

Optimal design of inerter-based isolators minimizing the compliance and mobility transfer function versus harmonic and random ground acceleration excitation

2020 ◽  
pp. 107754632094017
Author(s):  
Marcial Baduidana ◽  
Aurelien Kenfack-Jiotsa
Keyword(s):  
Transfer Function ◽  
Vibration Absorber ◽  
Engineering Practice ◽  
Primary System ◽  
Optimal Parameters ◽  
Dynamic Vibration Absorber ◽  
Ground Acceleration ◽  
Dynamic Vibration ◽  
Optimum Parameters ◽  
Peak Value

This study is concerned with the problem of analysis and optimization of inerter-based systems. A main inerter system is generally composed of an inerter, a spring, and viscous damper. Series – parallel inerter system s and series inerter system s are two commonly used configurations of inerter-based system s . First , in this study , the H∞ optimum parameters of inerter-based isolators are derived to minimize the compliance and mobility transfer function of a single-degree -of-freedom system under a harmonic ground acceleration excitation. Under the optimum tuning condition, it is shown that the proposed inerter-based isolators when compared with the traditional dynamic vibration absorber provide larger suppression of the peak value of the magnitude of compliance and mobility transfer function s of the primary system. For the studied cases, more than 40% and 45% improvement can be attained in terms of minimizing the compliance and mobility transfer function s , respectively, as compared with the traditional dynamic vibration absorber for the series – parallel inerter system and 15% and 11% improvement can be attained respectively , for the series inerter system . Finally, further comparison between the inerter-based isolators and traditional dynamic vibration absorber under white noise excitation also shows that the series – parallel inerter system and series inerter system s are superior to the traditional dynamic vibration absorber . The results of the studied systems show that m ore than 23% and 16% improvement are attained in terms of minimizing the compliance and mobility transfer function s respectively , as compared with the traditional dynamic vibration absorber for the series – parallel inerter system and 26% and 13% improvement can be attained respectively , for the series inerter system . The optimal parameters for different cases are obtained. It is shown that the optimal parameters obtained using the minimized mobility transfer function are smaller than those using the compliance transfer function at all mass ratios or inertance-to-mass ratio. The results of this study can provide theoretical basis for design of the optimal inerter-based isolators in engineering practice.

Application of Dynamic Vibration Absorbers to Mass Measurement

1997 ◽  
Author(s):  
Takeshi Mizuno
Keyword(s):  
Measurement System ◽  
Mass Measurement ◽  
Vibration Absorber ◽  
Rotational Axis ◽  
Automatic Frequency ◽  
Dynamic Vibration Absorber ◽  
Measuring Device ◽  
Supporting Structure ◽  
Dynamic Vibration ◽  
Auxiliary Mass

Abstract A mass measurement system which uses a dynamic vibration absorber as measuring device is developed. It can measure mass even under weightless conditions like in space stations. In this system, an object to be measured is fixed to a rotating table (rotor) at a distance from the rotational axis. Since it makes the rotor unbalanced, a centrifugal force causes the supporting structure to vibrate during rotation. A dynamic vibration absorber attached to the structure is tuned or controlled to cancel the excitation force. When the structure does not vibrate, the amplitude of motion of the auxiliary mass equals the ratio of the amount of unbalance to the auxiliary mass. Therefore, the mass of the object is determined from the motion of the auxiliary mass. According to the measurement principles, the vibration of the supporting structure must be eliminated. A servocompensator with the performance of automatic frequency tracking is applied to reduce the vibration. Experimental results demonstrate that mass can be measured accurately with the developed measurement system.

Parameter Design of Heave Compensation System of Deep-Sea Mining Based on Dynamic Vibration Absorber and its Experimental Study

2010 ◽  
Vol 34-35 ◽  
pp. 1999-2005
Author(s):  
Liu Jun Li ◽  
Shao Jun Liu ◽  
Jin Yu Zuo
Keyword(s):  
Deep Sea ◽  
Production Efficiency ◽  
Compensation System ◽  
Vibration Absorber ◽  
Random Wave ◽  
Dynamic Vibration Absorber ◽  
Mining System ◽  
Irregular Wave ◽  
Dynamic Vibration ◽  
Optimum Parameters

To ensure the safety and the production efficiency as well as the component lifetime of deep-sea mining system, a novel heave compensation system of deep-sea mining based on dynamic vibration absorber was proposed in the light of 5000m deep sea poly-metallic mining system of China in this paper. According to the work condition of heave compensation system, the response of deep-sea mining ship under random wave of sea state 4 in China’s deep sea poly-metallic mining field are numerically simulated in time domain. The proposed heave compensation system was simplified to a two-degree-of-freedom system stimulated by the displacement motion of the deep-sea mining ship and its dynamic model was built. Taking the minimum of the displacement variance of the proposed heave compensation system as the optimal object and considering the allowed displacement of the dynamic vibration absorber itself, the computation formula of the optimum parameters of dynamic vibration absorber for heave compensation system of deep-sea mining is derived. Thus the parameter of dynamic vibration absorber was determined and its effect on the performance index of the heave compensation system was simulated and compared. The dynamic vibration absorber with optimum parameters was simulated and tested on the test bench of double-storey mass-spring vibration system in the lab. The results of the example show that the performance of vibration control of the designed dynamic vibration absorber is satisfactory and the computational formulas given in the paper are effective. The results also verified that the heave compensator based on dynamic vibration absorber with the optimal parameters can have good performance of heave compensation and it is practical to isolate the lifting pipeline and its deployment platform from the vibration of the ship motion induced by the irregular wave with simplicity and less energy consumption. This work in the paper will be of great theoretical guidance in the optimum design of the dynamic vibration absorber for heave compensation system of deep-sea mining.

scholarly journals Effect of Inerter in Traditional and Variant Dynamic Vibration Absorbers for One Degree-of-Freedom Systems Subjected to Base Excitations

2019 ◽  
Vol 23 (1) ◽  
pp. 9-16
Author(s):  
Dheepakram Laxmimala Barathwaaj ◽  
Sujay Yegateela ◽  
Vivek Vardhan ◽  
Vignesh Suresh ◽  
Devarajan Kaliyannan
Keyword(s):  
Damping Ratio ◽  
Maximum Amplitude ◽  
Vibration Absorber ◽  
Primary System ◽  
Base Excitation ◽  
Mass Ratio ◽  
Magnification Factor ◽  
Dynamic Vibration Absorber ◽  
Optimum Frequency ◽  
Dynamic Vibration

Abstract In this paper, closed-form optimal parameters of inerter-based variant dynamic vibration absorber (variant IDVA) coupled to a primary system subjected to base excitation are derived based on classical fixed-points theory. The proposed variant IDVA is obtained by adding an inerter alone parallel to the absorber damper in the variant dynamic vibration absorber (variant DVA). A new set of optimum frequency and damping ratio of the absorber is derived, thereby resulting in lower maximum amplitude magnification factor than the inerter-based traditional dynamic vibration absorber (traditional IDVA). Under the optimum tuning condition of the absorbers, it is proved both analytically and numerically that the proposed variant IDVA provides a larger suppression of resonant vibration amplitude of the primary system subjected to base excitation. It is demonstrated that adding an inerter alone to the variant DVA provides 19% improvement in vibration suppression than traditional IDVA when the mass ratio is less than 0.2 and the effective frequency bandwidth of the proposed IDVA is wider than the traditional IDVA. The effect of inertance and mass ratio on the amplitude magnification factor of traditional and variant IDVA is also studied.

Research of Two-Series-Mass Dynamic Vibration Absorber and it’s Application on Building Vibration Control

2011 ◽  
Vol 368-373 ◽  
pp. 146-149
Author(s):  
Gong Yu Pan ◽  
Ying Zhang
Keyword(s):  
Vibration Control ◽  
Total Mass ◽  
Absorption Efficiency ◽  
Vibration Absorber ◽  
Mass Ratio ◽  
Dynamic Vibration Absorber ◽  
Vibration Absorption ◽  
Dynamic Vibration ◽  
Simulation And Experiment ◽  
Single Mass

Multiplexing the dynamic vibration absorber (DVA) has tried for improving the vibration absorption efficiency of the dynamic vibration absorber, and because there are several tuning vibration frequencies in the multi-mass dynamic vibration absorber system, the vibration absorption efficiency is more excellent than a conventional single-mass dynamic vibration absorber when they are in the same total mass ratio. In this paper, a two-series-mass dynamic vibration absorber was proposed, optimal parameters of the two-series-mass dynamic vibration absorber have been calculated and vibration absorption is analyzed with the simulation and experiment. The results show that the two-series-mss dynamic vibration absorber can improve vibration absorption, in the same total mass ratio, by about 20% above that of a conventional single-mass dynamic vibration absorber. Based on the above optimal results, the two-series-mass dynamic vibration was used for vibration control on high building, and the practical measure result shows its effectiveness.

An Optimal Design Method for Rubber Dynamic Vibration Absorber

1995 ◽  
Author(s):  
Yoshihiro Satoh ◽  
Hiroshi Misawa
Keyword(s):  
Optimal Design ◽  
Objective Function ◽  
Design Method ◽  
Vibration Absorber ◽  
Response Functions ◽  
Mass Ratio ◽  
Dynamic Vibration Absorber ◽  
Dynamic Vibration ◽  
Optimal Values ◽  
Optimal Design Method

Abstract A dynamic vibration absorber can be used for suppression of excessive amplitude of structures at the resonance. This paper deals with an optimal design method for the dynamic vibration absorber which consists of a mass and a carbon-black filled rubber vulcanizate. First, a system which consists of a main system and the dynamic vibration absorber was analyzed, considering nonlinear dynamic properties possessed by the rubber vulcanizate. Frequency response functions of the system were derived in the form including the rubber geometry and a mass ratio as design parameters. Next, an objective function was composed of the frequency response functions. Minimizing the objective function with respect to the parameters of the rubber geometry for given mass ratio, the optimal values were determined. From the consideration of the results, a new convenient method to determine the optimal values was derived. This method was examined by the experiments. As a result, the validity of the analysis method was verified, and the availability of the present design method for the suppression of vibration was confirmed.

Enhancement of a dynamic vibration absorber by means of an electromagnetic shunt

2020 ◽  
pp. 1045389X2095709
Author(s):  
Michel Auleley ◽  
Olivier Thomas ◽  
Christophe Giraud-Audine ◽  
Hervé Mahé
Keyword(s):  
Electromagnetic Coupling ◽  
Coupling Factor ◽  
Vibration Absorber ◽  
Mass Ratio ◽  
Structural Vibrations ◽  
Dynamic Vibration Absorber ◽  
Dynamic Vibration ◽  
Optimal Values ◽  
Theoretical Results ◽  
Good Agreement

In this study, we address the reduction of structural vibrations by means of an electromagnetic shunt damper (EMSD) combined with a mechanical dynamic vibration absorber (DVA). Two architectures, that differs in the placement of the EMSD with respect to the DVA, are tested, showing that one of them enhances the vibration control. In parallel, three shunt architecture are tested: a resistive shunt, a resonant conservative shunt and a resonant dissipative shunt. Optimal values of the EMSD and DVA parameters are obtained; then, the performances of all architecture, according to relevant criteria, are estimated and compared to a single DVA or a single EMSD. The case of a conservative DVA, that creates an anti-resonance, is particularly targeted. It is shown that the performances rely on two free parameters only: the mass ratio for the DVA and the electromagnetic coupling factor for the EMSD, thus giving generic abacuses that can be applied to any practical cases. Finally, experiments are proposed and a good agreement with the theoretical results is obtained, thus validating them.

Analytical and Experimental Evaluation of an Air Damped Dynamic Vibration Absorber: Design Optimizations of the Three-Element Type Model

1999 ◽  
Vol 121 (3) ◽  
pp. 334-342 ◽  
Author(s):  
Toshihiko Asami ◽  
Osamu Nishihara
Keyword(s):  
Maxwell Model ◽  
Element Model ◽  
Original Position ◽  
Vibration Absorber ◽  
Type Model ◽  
Dynamic Vibration Absorber ◽  
Dynamic Vibration ◽  
Spring Element ◽  
Optimum Parameters ◽  
Element Type

In this paper, we propose a dynamic vibration absorber (DVA) with an air damper consisting of a piston and a cylinder. First, it will be shown that the air damper can conveniently be represented by the Maxwell model where a spring element and a dashpot are connected in series. The air damper has no ability to return the piston to its original position. For this reason, it is necessary for the piston to be supported by a spring which is placed in parallel with the damper. The air damped DVA can then be modeled by the three-element model. Many studies have been done on the Voigt type of DVA, and the accurate expressions of optimum tuning and damping parameters have already been derived by Hahnkamm and Brock et al. However, only a few papers have been published on the three-element type of DVA, and reliable expressions for it have not been derived until now. Therefore, we began our work by trying to derive expressions for optimum parameters of the three-element type of DVA. It was clear that the optimized three-element type of DVA is superior to the conventional Voigt type of DVA. The optimum parameters which we obtained from our expressions were tested on a vibratory model. The experiments showed that the our expression is very useful for designing the air damped DVA.

Sign in / Sign up

Export Citation Format

Share Document