Dual-mass flywheels with tuned vibration absorbers for application in heavy-duty truck powertrains

Author(s):  
Lina Wramner

As the heavy-duty combustion engine development goes towards lower rotational speeds and higher cylinder pressures, the torsional vibrations increase. There is therefore a need to identify and study new types of vibration absorbers that can reduce the level of torsional vibrations transmitted from the engine to the gearbox. In this work, the concept of a dual-mass flywheel combined with a tuned vibration absorber is analysed. The tuned vibration absorber efficiently reduces the vibration amplitudes for engine load frequencies near the tuning frequency, but it also introduces an additional resonance into the system. By placing the tuned vibration absorber on an intermediate flange between the two dual-mass flywheels, the introduced resonance frequency will be lower than the tuning frequency and a resonance in operating engine speed range can be avoided. Numerical simulations are used to show how the torsional vibration amplitudes in a heavy-duty truck powertrain are affected by the tuned vibration absorber and how the different parameters of the tuned vibration absorber and the dual-mass flywheel affect the torsional vibrations and the resonance frequencies.

Author(s):  
Jeong-Hoi Koo ◽  
Medhi Ahmadian

The main purpose of this study is to offer a comprehensive off-tuning analysis of a semi-active tuned vibration absorber. A base-excited, single-degree-of-freedom structure with a tuned vibration absorber (TVA) model is adapted as the baseline model for our analysis. Moreover, a non-model based groundhook control (displacement based on-off control or "On-off DBG") is used to control the damping in the TVA. In order to study the effect of off-tuning, numerical models of the damping controlled TVA along with its equivalent passive TVA were developed. Using these models, the optimal tuning parameters of both TVA models were obtained based on minimization of peak transmissibility. The two optimally tuned models were then "off-tuned" by varying the primary structure's mass, stiffness, and damping. Using the peak transmissibility reduction criteria, the dynamic performances of the off-tuned TVAs were evaluated. The results indicate that the peak transmissibility of the semi-active TVA is about 20% lower than that of passive, implying that the semi-active TVA is more effective in reducing vibration levels. The results further indicate that the semi-active TVA is more robust to changes in primary structure mass and stiffness. In summary, the offtuning analyses of the semi-active TVA revealed the practical benefits of using it over the passive counterpart to structures subjected to changes in system parameters.


2020 ◽  
Vol 143 (1) ◽  
Author(s):  
Seon Il Ha ◽  
Gil Ho Yoon

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.


Author(s):  
Mark Holdhusen ◽  
Kenneth A. Cunefare

A state-switched absorber (SSA) is a device capable of instantaneously changing its stiffness, thus it can switch between resonance frequencies, increasing its effective bandwidth as compared to classical tuned vibration absorbers for vibration control. Previous numerical work has shown that an optimized SSA outperforms an optimized TVA at controlling vibrations of both a beam and a plate. This paper details the experimental validation of these simulation results. An SSA was realized by employing magneto-rheological elastomers to achieve a stiffness change. The stiffness of these elastomers is a function of the magnetic field put across them. Experiments were conducted on both a cantilever beam and a square plate clamped on all sides. Each system was excited by several two-frequency component excitations. For each forcing combination, several tuning configurations of the SSA were applied and the kinetic energy of the system was found. This observed performance was compared to the performance found through numerical simulations of a system with a similar tuning and excitation configuration. It was found that the observed performance follows closely with results found through numerical simulation.


1969 ◽  
Vol 91 (1) ◽  
pp. 282-287 ◽  
Author(s):  
A. V. Srinivasan

The analysis of parallel damped dynamic vibration absorbers is presented. The system considered is essentially a modification of the conventional damped vibration absorber and consists of adding, in parallel, a subsidiary undamped absorber mass in addition to the damped absorber mass. The analysis clearly shows that it is possible to obtain an undamped antiresonance in a dynamic absorber system which exhibits a well-damped resonance. While the bandwidth of frequencies between the damped peaks is not significantly increased, the amplitudes of the main mass are considerably smaller within the operational range of the absorber. The damped absorber mass and the main mass attain null simultaneously so that the vibratory force is transmitted directly to the undamped absorber. Numerical results are presented for the special case when the absorber masses have the same magnitude. Two cases of tuning have been considered: (a) when the absorber masses are tuned to the frequency of the main mass, and (b) when the absorber masses are tuned to the so-called favorable tuning frequency. Comparison of the results with those of the conventional absorber indicates that the parallel damped dynamic vibration absorber has definite advantages over the conventional damped vibration absorber.


2009 ◽  
Vol 62 (6) ◽  
Author(s):  
Lari Kela ◽  
Pekka Vähäoja

This article gathers together the most recent articles of adjustable tuned vibration absorbers. The tuned vibration absorber was invented over 100 years ago, and its adjustability is also already well-known. However, concentration of this review was only on articles published since the year 2000 in peer reviewed journals, except from certain elementary books and some previous review articles in order to keep up with the current events in this broad field. First a brief inspection of the theory of tuned vibration absorbers (TVAs) is presented. After that mechanical TVAs are presented more carefully. In the same chapter the following are also handled: virtual absorbers, absorbers with adjustable damping, and Helmholtz resonators. Own chapter is allocated for multiple TVAs whose idea is to replace adjustability by adding several TVAs to primary system to damp out vibrations in the wide frequency band. The review section is completed by presenting smart material TVAs, which include, e.g., piezoelectric materials, shape-memory alloys, electrorheological and magnetorheological materials of fluids. An adjustable Helmholtz resonator in a low pressure hydraulic system is presented in Sec. 5. Experiments verify the efficiency of the damping character of the adjustable Helmholtz resonator whose resonant frequency can be varied.


Author(s):  
Mark H. Holdhusen ◽  
Kenneth A. Cunefare

A State-Switched Absorber (SSA) is a device capable of instantaneously changing its stiffness, thus it can switch between resonance frequencies, increasing its effective bandwidth as compared to classical tuned vibration absorbers for vibration control. Previous theoretical simulations show that for a system subjected to a multi-harmonic disturbance, using an appropriate logic for switching states, the SSA reduces vibration more effectively than classical tuned vibration absorbers (TVA). This paper considers the experimental performance of the SSA for vibration suppression of an elastically mounted lumped mass base. State switching is achieved using magneto-rheological fluid to connect or disconnect a coil spring in parallel with other coil springs. The stiffness state is controlled by applying or removing a magnetic field across of the MR fluid. Experiments were performed over a range of forcing and tuning frequencies. The SSA system, optimally tuned, outperformed the optimal classical TVA system for all combinations of forcing frequencies.


2006 ◽  
Vol 13 (4-5) ◽  
pp. 531-543 ◽  
Author(s):  
Michael J. Brennan

The vibration absorber has been used for vibration control purposes in many sectors of engineering from aerospace, to automotive to civil, for the past 100 years or so. A limitation of the device, however, is that it acts like a notch filter, only being effective over a narrow band of frequencies. Recent developments have overcome this limitation by making it possible to tune the device over a range of frequencies. This has been achieved by incorporating a variable stiffness element that can be adjusted in real-time. In this paper, some ways in which stiffness change can be achieved in practice are reviewed and some examples of prototype adaptive tuned vibration absorbers (ATVAs) are described. A simple control scheme to automatically tune an ATVA is also presented.


2000 ◽  
Author(s):  
Kenneth A. Cunefare

Abstract A system that has the capability to make instantaneous changes in its mass, stiffness, or damping may be termed a state-switchable dynamical system. Such a system will display different dynamical responses dependent upon its current state. State-switchable stiffness may be practically obtained through the control of the termination impedance of piezoelectric stiffness elements. If such a switchable stiffness element is incorporated as part of the spring element of a vibration absorber, the change in stiffness causes a change in the resonance frequencies of the system, thereby instantaneously ‘retuning’ the state-switched absorber to a new frequency. In between state switches, the operation of such a device is passive, being fundamentally a passive vibration absorber. This concept has improved performance over classical passive vibration absorbers or dampers, particularly for disturbances with multiple spectral components. This paper considers the application of such a device for the purpose of vibration control on beams subjected to harmonic point-force excitation.


Author(s):  
Mainak Mitra ◽  
Andrea Lupini ◽  
Bogdan I. Epureanu

Abstract The vibration absorber or tuned mass damper is a well-known mechanism, where a small mass connected to a larger structure is used to redirect vibration energy and provide reduction in vibration amplitudes at desired locations and frequencies. While tuned vibration absorbers have been widely applied for damping of mechanical systems, the concept remains largely unexplored in the design of dampers for bladed disks. This paper investigates whether such a vibration absorption mechanism is feasible for such nominally cyclic symmetric structures which are characterized by double modes, high modal density, and sensitivity to uncertainties such as mistuning. The single-degree of freedom vibration absorber concept is extended for application to this complex modal space, and lumped mass models are used for analysis. Trends in effectiveness of a vibration absorption based damper are explored by studying sensitivities to various parameters such as stiffness and damping at various locations. Effects of mistuning across sectors and locations of damper attachment are also considered. The results of the study establish the feasibility of the vibration absorption mechanism for application in blisks, and encourage further exploration of the concept, possibly in conjunction with other well-established damping mechanisms such as friction.


Vibration ◽  
2019 ◽  
Vol 2 (3) ◽  
pp. 240-264 ◽  
Author(s):  
Viktor Berbyuk

In this paper, the feasibility of the application of a dual mass flywheel (DMF) for heavy-duty truck drivetrain systems was studied. The third engine order vibration harmonic was in the focus of analysis as one of the most significant contributions to the oscillatory response in the drivetrain systems of heavy-duty trucks. Global sensitivity analysis (GSA) and Pareto optimization were used for designing torsional vibration absorbers in an operating engine speed range of 600–2000 rpm. The optimization method attempted both to minimize the oscillations of the torque at the transmission input shaft and to maximize the energy efficiency of the vibration absorber. The GSA enabled the appropriate scanning of the domain of design parameters by varying all the parameters at the same time. It provided deep insight into the design process and increased the computational efficiency of the optimization. The results obtained show the following: the solution of the bi-objective optimization problem for torsional vibration absorbers does exist; Pareto fronts were obtained and analyzed for the DMF, presenting a trade-off between the measure of the attenuation of the oscillations of the torque at the transmission input shaft and the measure of the energy efficiency of the absorber; the optimized mass inertia, stiffness and damping parameters of a DMF do exist, providing the best attenuation of the torque oscillations; the performance of a DMF was further enhanced by incorporating a torsional tuned mass damper with appropriate optimized parameters. Finally, the results show evidence of the feasibility of the application of dual mass flywheels in heavy-duty truck drivetrain systems.


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