scholarly journals Optimal parameters of tuned mass dampers for machine shaft using the maximum equivalent viscous resistance method

2020 ◽  
Vol 14 (1) ◽  
pp. 127-135 ◽  
Author(s):  
Nguyen Duy Chinh
Keyword(s):  
Torsional Vibration ◽  
Vibration Reduction ◽  
Tuned Mass Damper ◽  
Random Excitation ◽  
Viscous Resistance ◽  
Optimal Parameters ◽  
Tuned Mass Dampers ◽  
Specific Data ◽  
Resistance Method ◽  
Mass Damper

The paper analyzes and determines the optimal parameters of tuned mass damper to reduce torsional vibration for the machine shaft. The research steps are as follows. First, the optimal parameters of tuned mass damper for the shafts are given by using the maximization of equivalent viscous resistance method. Second, a numerical simulation is performed for configuration of machine shaft to validate the effectiveness of the obtained analytical results. The simulation results indicate that the proposed method significantly increases the effectiveness of torsional vibration reduction. Optimal parameters include the ratio between natural frequency of tuned mass damper and the machine shaft, the ratio of the viscous coefficient of tuned mass damper. The optimal parameters found by numerical method only apply to a machine shaft with specific data. However, the optimal parameters in this paper are found as analytic and explicit to help scientists easily apply to every machine shafts when the input parameters of the machine shaft change. Keywords: tuned mass damper; torsional vibration; optimal parameters; random excitation; equivalent viscous resistance.

Determination of optimal parameters of the tuned mass damper to reduce the torsional vibration of the shaft by using the principle of minimum kinetic energy

2018 ◽  
Vol 233 (2) ◽  
pp. 327-335 ◽  
Author(s):  
Duy-Chinh Nguyen
Keyword(s):  
Kinetic Energy ◽  
Torsional Vibration ◽  
Damping Ratio ◽  
Vibration Reduction ◽  
Tuned Mass Damper ◽  
Optimal Parameters ◽  
Lagrangian Equations ◽  
Tuning Ratio ◽  
Mass Damper

In this paper, an analytical method is presented to determine the optimal parameters of the symmetric tuned mass damper, such as the ratio between natural frequency of tuned mass damper and shaft (tuning ratio) and the ratio of the viscous coefficient of tuned mass damper (damping ratio). The optimal parameters of tuned mass damper are applied to reduce the torsional vibration of the shaft based on consideration of the vibration duration and stability criterion. The dynamic equations of the shaft are provided via Lagrangian equations, and the optimal parameters of tuned mass damper are derived by using the principle of minimum kinetic energy. Analytical and numerical examples are implemented to verify the reliability of the proposed method. The analytical and numerical results indicate that the optimal parameters of tuned mass damper have significant effects in the torsional vibration reduction of the shaft.

Optimal parameters of tuned mass dampers for an inverted pendulum with two degrees of freedom

2020 ◽  
pp. 146441932097108
Author(s):  
Duy-Chinh Nguyen
Keyword(s):  
Degrees Of Freedom ◽  
Inverted Pendulum ◽  
Tall Buildings ◽  
Viscous Resistance ◽  
Optimal Parameters ◽  
Tuned Mass Dampers ◽  
Two Degrees Of Freedom ◽  
Resistance Method ◽  
Parametric Studies ◽  
Frequency Ratios

In reality, an inverted pendulum can be used to model many real structures as the fluid tower, super-tall buildings, or articulated tower in the ocean, etc. However, for the inverted pendulum with two degrees of freedom, to the best knowledge of the author, there is no study to determine optimal parameters of two tuned mass dampers (TMD) by using the maximization of equivalent viscous resistance method. Therefore, the current study presents the analytical solutions to the optimization of two orthogonal TMDs, which is used to eliminate vibration of the inverted pendulum with two degrees of freedom. The parameters considered in optimizing are the natural frequency ratios and damping ratios of the two TMDs. The new results of this paper can be summarized as follows: Firstly, the equivalent resistance forces of the two TMDs acting on the inverted pendulum with two degrees of freedom are established. Secondly, the quadratic torque matrices of the vibration response of the inverted pendulum attached with two TMDs is revealed. Thirdly, the optimal expressions are derived using the maximization of equivalent viscous resistance method. The obtained formulae provide exact solutions for the proposed problem. Finally, to confirm the effectiveness of the obtained formulae, parametric studies on vibration are performed for sample articulated tower in the ocean with and without optimal TMDs. Numerical results show that vibrations of the articulated tower attached with optimal TMDs are effectively eliminated. This confirms that the optimal parameters of the two TMDs are determined in this paper are reliable and accurate.

scholarly journals Parametric Study of Tuned Mass Dampers for Long Span Transmission Tower-Line System under Wind Loads

2016 ◽  
Vol 2016 ◽  
pp. 1-11 ◽  
Author(s):  
Li Tian ◽  
Yujie Zeng
Keyword(s):  
Frequency Ratio ◽  
Damping Ratio ◽  
Vibration Reduction ◽  
Tuned Mass Damper ◽  
Reduction Ratio ◽  
Transmission Tower ◽  
Tuned Mass Dampers ◽  
Line System ◽  
Long Span ◽  
Mass Damper

A parametric study of tuned mass dampers for a long span transmission tower-line system under wind loads is done in this paper. A three-dimensional finite element model of transmission tower-line system is established by SAP2000 software to numerically verify the effectiveness of the tuned mass damper device. The wind load time history is simulated based on Kaimal spectrum by the harmony superposition method. The equations of motion of a system with tuned mass damper under wind load excitation are proposed, and the schematic of tuned mass damper is introduced. The effects of mass ratio, frequency ratio, damping ratio, the change of the sag of transmission line, and the robustness of TMD are investigated, respectively. Results show that(1)the change of mass ratio has a greater effect on the vibration reduction ratio than those of frequency ratio and damping ratio, and the best vibration reduction ratio of TMD is not the frequency ratio of 1;(2)the sag-span ratio has an insignificant effect on the vibration reduction ratio of transmission tower when the change of sag-span ratio is not large; and(3)the effect of ice should be considered when the robustness study of TMD is carried out.

Design of the symmetric tuned mass damper for torsional vibration control of the rotating shaft

2021 ◽  
pp. 095745652110004
Author(s):  
Duy-Chinh Nguyen
Keyword(s):  
Angular Velocity ◽  
Vibration Control ◽  
Fixed Points ◽  
Torsional Vibration ◽  
Tuned Mass Damper ◽  
Constant Angular Velocity ◽  
Optimal Parameters ◽  
Rotating Shaft ◽  
Mass Damper

The shaft is one of the most important parts of the machine, and it is used to transmit torque. However, the shaft does not always rotate at constant angular velocity due to sudden acceleration or deceleration or due to unstable current. The rotation of the shaft varies with time, which causes torsional vibration on the rotating shaft. To the best of the author’s knowledge, there is no study on designing a symmetric tuned mass damper (STMD) for the rotating shaft with variable angular velocity. Therefore, the purpose of this study is to design an optimal STMD to reduce torsional vibration for the rotating shaft with variable angular velocity. First, the author designs an optimal STMD for the rotating shaft by the fixed-points theory. Second, the optimal parameters of the STMD are obtained by using the minimum quadratic torque method. The optimal parameters of the STMD are defined in analytic and explicit forms, helping researchers to easily design an optimal STMD when applying to reduce torsional vibration for the rotating shaft. Finally, to evaluate the reliability of the designed optimal STMD, Maple software is used to simulate the vibration of the rotating shaft attached with the optimal STMD, as well as to help the readers to have a visual view on the effect of reducing torsional vibration of the rotating shaft.

Effectiveness of Location and Number of Multiple Tuned Mass Damper for Seismic Structures

2020 ◽  
Vol 9 (6) ◽  
pp. 780-783
Keyword(s):  
Seismic Response ◽  
Software Tool ◽  
Tuned Mass Damper ◽  
Structure Study ◽  
Structural Performance ◽  
Mass Ratio ◽  
Tuned Mass Dampers ◽  
Maximum Reduction ◽  
Mass Damper ◽  
Earthquake Data

Tuned mass dampers (TMD) are one of the most reliable devices to control the vibration of the structure. The optimum mass ratio required for a single tuned mass damper (STMD) is evaluated corresponding to the fundamental natural frequency of the structure. The effect of STMD and Multiple tuned mass dampers (MTMD) on a G+20 storey structure are studied to demonstrate the damper’s effectiveness in seismic application. The location and number of tuned mass dampers are studied to give best structural performance in maximum reduction of seismic response for El Centro earthquake data. The analysis results from SAP 2000 software tool shows damper weighing 2.5% of the total weight of the structure effectively reduce the response of the structure. Study shows that introduction of 4-MTMD at top storey can effectively reduce the response by 10% more in comparison to single tuned mass damper. The use of MTMD of same mass ratio that of STMD is more effective in seismic response.

Adaptive multiple tuned mass dampers based on modal parameters for earthquake response reduction in multi-story buildings

2016 ◽  
Vol 20 (9) ◽  
pp. 1375-1389 ◽  
Author(s):  
Mohammad Sabbir Rahman ◽  
Md Kamrul Hassan ◽  
Seongkyu Chang ◽  
Dookie Kim
Keyword(s):  
Tuned Mass Damper ◽  
Primary Objective ◽  
Modal Parameters ◽  
Earthquake Response ◽  
Tuned Mass Dampers ◽  
Mass Damper ◽  
Modal Mass ◽  
Story Building ◽  
Selection Of ◽  
Multiple Tuned Mass Dampers

The primary objective of this research is to find the effectiveness of an adaptive multiple tuned mass damper distributed along with the story height to control the seismic response of the structure. The seismic performance of a 10-story building was investigated, which proved the efficiency of the adaptive multiple tuned mass damper. Structures with single tuned mass damper and multiple tuned mass dampers were also modeled considering the location of the dampers at the top of the structure, whereas adaptive multiple tuned mass damper of the structure was modeled based on the story height. Selection of the location of the adaptive multiple tuned mass damper along with the story height was dominated by the modal parameters. Participation of modal mass directly controlled the number of the modes to be considered. To set the stage, a comparative study on the displacements and modal energies of the structures under the El-Centro, California, and North-Ridge earthquakes was conducted with and without various types of tuned mass dampers. The result shows a significant capability of the proposed adaptive multiple tuned mass damper as an alternative tool to reduce the earthquake responses of multi-story buildings.

Back-iron design-based electromagnetic regenerative tuned mass damper

2020 ◽  
Vol 234 (3) ◽  
pp. 607-622
Author(s):  
Semen Kopylov ◽  
Zhaobo Chen ◽  
Mohamed AA Abdelkareem
Keyword(s):  
Root Mean Square ◽  
Tuned Mass Damper ◽  
Harmonic Excitation ◽  
Experimental Results ◽  
Mean Square ◽  
Tuned Mass Dampers ◽  
Practical Applications ◽  
Mass Damper ◽  
Compact Dimension ◽  
Regenerative Power

Implementation of tuned mass dampers is the commonly used approach to avoid excessive vibrations in civil engineering. However, due to the absence of the compact dimension, there are still no practical applications of the tuned mass dampers in automotive industry. Meanwhile, recent investigations showed the benefit of utilizing a tuned mass damper in a vehicle suspension in terms of driving comfort and road holding. Thus, the current investigation aimed to explore a novel compact dimension tuned mass damper, which can provide both sufficient vibration mitigation and energy harvesting. This paper presents a prototype of a back-iron-based design of an electromagnetic regenerative tuned mass damper. The mathematical model of the tuned mass damper system was developed and has been validated by the experimental results of the tuned mass damper prototype implemented in a protected mass test-bench. The indicated results concluded that the attenuation performance dramatically deteriorated under random excitations and a reduction in the root-mean-square acceleration of 18% is concluded compared to the case with undamped tuned mass damper. Under harmonic excitations, the designed tuned mass damper prototype is able to reduce the peak acceleration value of the protected structure by 79%. According to the experimental results, the designed tuned mass damper prototype revealed a peak regenerative power of 0.76 W under a harmonic excitation of 8.1 Hz frequency [Formula: see text]m amplitude. Given the simulated random road profiles from C to E, the back-iron electromagnetic tuned mass damper indicated that root-mean-square harvested power from 0.6 to 6.4 W, respectively.

Optimizing tuned mass damper parameters to mitigate the torsional vibration of a suspension bridge under pulse-type ground motion: A sensitivity analysis

2019 ◽  
Vol 26 (11-12) ◽  
pp. 1054-1067 ◽  
Author(s):  
Seyyed Hossein Hossein Lavassani ◽  
Hamed Alizadeh ◽  
Peyman Homami
Keyword(s):  
Sensitivity Analysis ◽  
Torsional Vibration ◽  
Passive Control ◽  
Suspension Bridge ◽  
Tuned Mass Damper ◽  
Gyration Radius ◽  
Suspension Bridges ◽  
Torsional Mode ◽  
Mass Damper ◽  
Pulse Type

Suspension bridges are structures that because of their long span and high flexibility can be prone to ambient vibrations such as ground motions. They can experience high amplitude vibrations in torsional mode during an earthquake, where a vibration control strategy seems necessary. Recently, control systems have been widely used to mitigate vibration of structures. Tuned mass damper is a passive control system. Its performance and effectiveness have been verified both theoretically and practically. In this study, a tuned mass damper system is used to mitigate the torsional vibration of a suspension bridge. The Vincent Thomas suspension bridge is selected as a case study, and its response is reduced by a tuned mass damper under ten pulse-type records from 10 major worldwide earthquakes. By using sensitivity analysis, a parametric study is carried out to optimize tuned mass damper parameters, namely, mass ratio, gyration radius, tuning frequency, and damping ratio according to the maximum reduction of the response maxima. Finally, the optimum range of each parameter that can give the best performance and provide both operational and economic justification for the implementation of the project is suggested. The numerical results indicate that the optimized tuned mass damper system can substantially reduce the maximum response and vibration time.

Analytical analysis for the design of nonlinear tuned mass damper

2020 ◽  
Vol 26 (9-10) ◽  
pp. 646-658
Author(s):  
Lu-yu Li ◽  
Tianjiao Zhang
Keyword(s):  
Passive Control ◽  
Design Method ◽  
Tuned Mass Damper ◽  
Control Device ◽  
Control Performance ◽  
Tuned Mass Dampers ◽  
Mass Damper ◽  
Practical Engineering ◽  
Optimum Formula ◽  
Nonlinear Tuned Mass Damper

A tuned mass damper is a passive control device that has been widely used in aerospace, mechanical, and civil engineering as well as many other fields. Tuned mass dampers have been studied and improved over the course of many years. In practical engineering applications, a tuned mass damper inevitably produces some nonlinear characteristics due to the large displacement and the use of the limiting devices, but this nonlinearity is often neglected. The simulation results in this study confirm that neglecting the nonlinearity in the design process can produce adverse effects on the control performance. This paper takes into account the nonlinearity of the tuned mass damper produced in the process of vibration and deduces an optimum formula for the frequency of a tuned mass damper by the complexification averaging method and multiscale method. Based on this formula, a modified design method for the frequency of a tuned mass damper is presented. The numerical results show that the nonlinear tuned mass damper after modification is better than a linear tuned mass damper in terms of control performance.

Sign in / Sign up

Export Citation Format

Share Document