scholarly journals Influence of Variable Damping Coefficient on Efficiency of TMD with Inerter

Energies ◽  
2020 ◽  
Vol 13 (23) ◽  
pp. 6175
Author(s):  
Piotr Brzeski ◽  
Mateusz Lazarek ◽  
Przemyslaw Perlikowski
Keyword(s):  
Oscillation Amplitude ◽  
Maximum Amplitude ◽  
Relative Displacement ◽  
Tuned Mass Damper ◽  
Damping Coefficient ◽  
Main Body ◽  
Mass Damper ◽  
Different Types ◽  
Non Linear ◽  
Variable Damping

In this paper, we study the dynamics of a two-degree freedom system consisting of the main body and tuned mass damper with inerter (TMDI). We add the dash-pot with variable damping coefficient to TMDI to study the overall efficiency of the device. We investigate different types of the non-linear characteristic of the dash-pot. We investigate devices in which damping coefficient change according to the relative displacement or the relative velocity between the damped mass and tuned mass damper. We also include in the investigation of different types of control functions. We show the two-parameter diagrams presenting the main body’s maximum amplitude versus the frequency of excitation of the damped body and different control parameter. We show how the application of a non-linear damper lets us control the main system’s oscillation amplitude.

scholarly journals Influence of dash-pot with controllable damping coefficient on damping efficiency of TMDI

2018 ◽  
Vol 148 ◽  
pp. 02001 ◽  
Author(s):  
Mateusz Lazarek ◽  
Piotr Brzeski ◽  
Przemyslaw Perlikowski
Keyword(s):  
Maximum Amplitude ◽  
Relative Displacement ◽  
Tuned Mass Damper ◽  
Damping Coefficient ◽  
Main Body ◽  
Controlling Parameter ◽  
Linear Characteristic ◽  
Mass Damper ◽  
Variable Damping ◽  
Two Parameters

In this paper we study the dynamics of two degree freedom system, which is consist of main body and tuned mass damper with inerter (TMDI). We add the dash-pot with variable damping coefficient to TMDI to study the overall efficiency of the device. The shape of non-linear characteristic of the dash-pot is dependent on one control parameter which governs the steepness of the function and the value of damping coefficient changes according to the relative displacement or velocity between main mass and tuned mass damper. We show the two parameters diagrams showing the maximum amplitude of the main body versus frequency of excitation of main body and controlling parameter.

Effects of Tuned Mass Damper on Fixed-Fixed 3D Nonlinear String Resting on Nonlinear Elastic Foundation

2017 ◽  
Vol 17 (04) ◽  
pp. 1750047 ◽  
Author(s):  
Yi-Ren Wang ◽  
Li-Ping Wu
Keyword(s):  
Elastic Foundation ◽  
Internal Resonance ◽  
Multiple Scales ◽  
Equations Of Motion ◽  
Maximum Amplitude ◽  
Tuned Mass Damper ◽  
Mode Shapes ◽  
Nonlinear Elastic Foundation ◽  
Mass Damper ◽  
Nonlinear Elastic

This paper studies the vibration of a nonlinear 3D-string fixed at both ends and supported by a nonlinear elastic foundation. Newton’s second law is adopted to derive the equations of motion for the string resting on an elastic foundation. Then, the method of multiple scales (MOMS) is employed for the analysis of the nonlinear system. It was found that 1:3 internal resonance exists in the first and fourth modes of the string when the wave speed in the transverse direction is [Formula: see text] and the elasticity coefficient of the foundation is [Formula: see text]. Fixed point plots are used to obtain the frequency responses of the various modes and to identify internal resonance through observation of the amplitudes and mode shapes. To prevent internal resonance and reduce vibration, a tuned mass damper (TMD) is applied to the string. The effects of various TMD masses, locations, damper coefficients ([Formula: see text]), and spring constants ([Formula: see text]) on overall damping were analyzed. The 3D plots of the maximum amplitude (3D POMAs) and 3D maximum amplitude contour plots (3D MACPs) are generated for the various modes to illustrate the amplitudes of the string, while identifying the optimal TMD parameters for vibration reduction. The results were verified numerically. It was concluded that better damping effects can be achieved using a TMD mass ratio [Formula: see text]–0.5 located near the middle of the string. Furthermore, for damper coefficient [Formula: see text], the use of spring constant [Formula: see text]–13 can improve the overall damping.

scholarly journals Non-linear dynamic response of a cable system with a tuned mass damper to stochastic base excitation via equivalent linearization technique

Meccanica ◽  
2020 ◽  
Vol 55 (12) ◽  
pp. 2413-2422 ◽  
Author(s):  
Hanna Weber ◽  
Stefan Kaczmarczyk ◽  
Radosław Iwankiewicz
Keyword(s):  
Tuned Mass Damper ◽  
Equivalent Linearization ◽  
Base Excitation ◽  
Cable System ◽  
Linearization Technique ◽  
Linear Dynamic ◽  
Transverse Modes ◽  
Mass Damper ◽  
Non Linear ◽  
Host Structure

AbstractNon-linear dynamic model of a cable–mass system with a transverse tuned mass damper is considered. The system is moving in a vertical host structure therefore the cable length varies slowly over time. Under the time-dependent external loads the sway of host structure with low frequencies and high amplitudes can be observed. That yields the base excitation which in turn results in the excitation of a cable system. The original model is governed by a system of non-linear partial differential equations with corresponding boundary conditions defined in a slowly time-variant space domain. To discretise the continuous model the Galerkin method is used. The assumption of the analysis is that the lateral displacements of the cable are coupled with its longitudinal elastic stretching. This brings the quadratic couplings between the longitudinal and transverse modes and cubic nonlinear terms due to the couplings between the transverse modes. To mitigate the dynamic response of the cable in the resonance region the tuned mass damper is applied. The stochastic base excitation, assumed as a narrow-band process mean-square equivalent to the harmonic process, is idealized with the aid of two linear filters: one second-order and one first-order. To determine the stochastic response the equivalent linearization technique is used. Mean values and variances of particular random state variable have been calculated numerically under various operational conditions. The stochastic results have been compared with the deterministic response to a harmonic process base excitation.

Damping Effect of Pendulum Tuned Mass Damper on Vibration of Two-Dimensional Rigid Body

2015 ◽  
Vol 15 (02) ◽  
pp. 1450041 ◽  
Author(s):  
Yi-Ren Wang ◽  
Ko-En Hung
Keyword(s):  
Rigid Body ◽  
Internal Resonance ◽  
Multiple Scales ◽  
Tuned Mass Damper ◽  
Contour Plot ◽  
Main Body ◽  
Two Dimensional ◽  
Damping Effect ◽  
Eigen Analysis ◽  
Mass Damper

This study investigated the effect of a pendulum tuned mass damper (PTMD) on the vibration of a slender two-dimensional (2D) rigid body with 1:2 internal resonance. Focus is placed on the damping effect of various parameters of the PTMD on preventing the internal resonance of the system. The instruments used include fixed points plots, time response and Poincaré maps, which were compared for confirmation of accuracy. The Lagrange's equation is employed to derive the equations of motion for the system. The method of multiple scales (MOMS) is applied to analyzing this nonlinear vibration model. The internal resonance conditions of the rigid body in vibration are obtained by the eigen-analysis. Moreover, a 3D internal resonance contour plot (3D-IRCP) aided by various amplitude analysis tables is proposed for identification of the parameter combinations of the PTMD for preventing internal resonance. This approach enables the designers to evaluate the effectiveness of various parameter combinations of the PTMD prior to the design process. The present study indicates that without changing the main configuration, the vibration amplitudes in the main body can be greatly reduced under certain parameter combinations of the PTMD.

Pendulum tuned mass dampers and tuned mass dampers: Analogy and optimum parameters for various combinations of response and excitation parameters

2021 ◽  
pp. 107754632110034
Author(s):  
Payam Soltani ◽  
Arnaud Deraemaeker
Keyword(s):  
Transfer Functions ◽  
Tuned Mass Damper ◽  
Tuned Mass Dampers ◽  
Earthquake Excitation ◽  
Optimum Parameters ◽  
Mass Damper ◽  
Different Types ◽  
Host Structure ◽  
Mass Spring ◽  
Tuning Rules

This study deals with the optimisation of pendulum tuned mass damper parameters for different types of excitations and responses of the host structure to which it is attached. The study considers force excitation and base excitation with different types of output quantities to be minimised on the host structure. It also considers both harmonic motion with H ∞ optimisation of the different transfer functions and random white noise excitation where the variance of the output signal is minimised, leading to H2 optimisation. Although a lot of work has been done on optimisation of tuned mass dampers, there exists in the literature only a few solutions for optimisation of the pendulum tuned mass dampers not covering all possible types of loads and output quantities. The analogy between the mass spring tuned mass damper and pendulum tuned mass damper presented in this study allows to use all the tuning rules developed for tuned mass dampers in the case of pendulum tuned mass dampers. In addition, the existing tuning rules for tuned mass dampers are extended to cases which were not previously solved in the literature for H2 optimisation and validated by comparing with numerical optimisation. Finally, a discussion is presented where the different tuning rules are compared, and the performance degradation is assessed when the wrong tuning rule is used. This is representative of the case where, for example, both wind and earthquake excitation exist on the structure, and the pendulum tuned mass damper is tuned for just wind excitation.

scholarly journals Study on Adaptive-Passive and Semi-Active Eddy Current Tuned Mass Damper with Variable Damping

2018 ◽  
Vol 10 (2) ◽  
pp. 99 ◽  
Author(s):  
Weixing Shi ◽  
Liangkun Wang ◽  
Zheng Lu ◽  
Hui Gao
Keyword(s):  
Eddy Current ◽  
Tuned Mass Damper ◽  
Mass Damper ◽  
Variable Damping

GA-Optimized Fuzzy State Space Model of Multi Degree Freedom Structure Under Seismic Excitation

2017 ◽  
Author(s):  
Thang Pham Huu ◽  
Akira Sone ◽  
Nanako Miura
Keyword(s):  
Fuzzy Logic ◽  
Structural Control ◽  
Fuzzy Logic Controller ◽  
Tuned Mass Damper ◽  
Structural System ◽  
Active Structural Control ◽  
Linear Behavior ◽  
Mass Damper ◽  
Non Linear ◽  
Fuzzy State

Active structural control has drawn significant attention in recent decades. In this paper, the problem of active vibration control of multi-degree-freedom structures is considered. Fuzzy logic controller combined with the genetic algorithm (GA) is designed to optimize the parameters of active tuned mass damper (ATMD) for the best results in reduction of the building response under earthquake excitation. The advantage of the fuzzy logic approach is the ability to handle the non-linear behavior of the system. Non-linear behavior of the soil is modeled in the dynamics of the structural system with nonlinear hysteric restoring forces. The building structure with eleven stories is modeled as a 2D frame, which uses tuned mass damper subsystems mounted on the top of the building. A structural system was simulated against the ground motion of the destructive earthquakes. The time history of the story displacements and accelerations, the control voltages and forces, and the frequency responses of both the uncontrolled and the controlled structures are shown in the end of this study. The performance of designed fuzzy logic control is checked using the changing mass parameters of each story and the results are discussed. The comparison between the proposed control and TMD passive control shows that the proposed fuzzy logic controller has great potential in active structural control.

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