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1

Reducing Noised – The Impact of Biocomposite Noise Dampers with Grinting Grass (Cynodon dactylon) on Noise Intensity

Rinawati Seviana, Khusaini Muh., Ciptadi Gatot, Handayani Dian

Ecological Engineering & Environmental Technology

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2024

|

Vol. 25, iss. 12

346--355

EN

The use of machines and technology in the industrial sector has led to noise pollution, which requires attention. The practice of noise control through soundproofing is closely linked to the use of various acoustic materials, whether they are synthetic or natural fibers. Natural materials are preferred for biocomposite reinforcement due to the design flexibility, eco-friendliness, sustainability, and ease of availability. Therefore, this research aimed to analyze the variation of grinting grass (Cynodon dactylon) composite material as damper with safe working distance from noise exposure. This experimental research was conducted using industrial grinding machine and damper from grinting grass as the object and composite material. The instruments used for measurement included an Impedance tube (sound absorption coefficient), a sound level meter (noise intensity), and a Surfer 13 noise mapping application. The data obtained were analyzed using the Wilcoxon test to determine the differences before and after the intervention. The results showed that the most effective composite had a 60:40 ratio with a sound absorption coefficient of 0.30. Before using damper, the highest noise intensity recorded was 106 dBA, which was reduced to 83 dBA. Safe working distance from exposure before damper was 6.1 meters, which decreased to 1 meter after the intervention. In conclusion, there was a significant difference in noise intensity (p = 0.000) and safe working distance from exposure (p = 0.001) before and after the use of grinting grass as damper.

2

Development of a Vibration Isolator on the Basis of a Magneto-Rheological Elastomer

Priyandoko Gigih, Hunaini Fachruddin, Imaduddin Fitrian, Ubaidillah Ubaidillah, Suwandono Purbo, Sasongko Muhammad Ilman Nur

Advances in Science and Technology. Research Journal

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2024

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Vol. 18, no. 8

272--280

EN

Magnetorheological elastomers (MREs) are smart materials. Their rheological properties can be controlled by applying an external magnetic field. MRE is a solid rubbery material that can change its modulus through the application of a magnetic field. This article presents the research on the simulation, manufacturing, and testing of vibration insulators. The first step in MRE vibration isolator design. A sufficient magnetic field for the stiffness change is considered in the material selection of the vibration isolator. The effectiveness of electromagnetic circuits in generating magnetic fields to minimize vibration is demonstrated using Finite Element Method Magnetics software. A vibration isolator test rig is installed as a second step. Lastly, different effects of current input on MRE isolators have been examined. The higher current input is more effective in eliminating vibration using the MRE isolation system.

3

Feasibility study of a rail vehicle damper fault detection by artificial neural networks

Melnik Rafał, Koziak Seweryn, Dižo Ján, Kuźmierowski Tomasz, Piotrowska Ewa

Eksploatacja i Niezawodność

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2023

|

Vol. 25, no. 1

art. no. 5

EN

The aim of the study was to investigate rail vehicle dynamics under primary suspension dampers faults and explore possibility of its detection by means of artificial neural networks. For these purposes two types of analysis were carried out: preliminary analysis of 1 DOF rail vehicle model and a second one - a passenger coach benchmark model was tested in multibody simulation software - MSC.Adams with use of VI-Rail package. Acceleration signals obtained from the latter analysis served as an input data into the artificial neural network (ANN). ANNs of different number of hidden layers were capable of detecting faults for the trained suspension fault cases, however, achieved accuracy was below 63% at the best. These results can be considered satisfactory considering the complexity of dynamic phenomena occurring in the vibration system of a rail vehicle.

4

The influence of shock absorber characteristics’ nonlinearities on suspension Frequency Response Function estimation and possibilities of simplified characteristics modelling

Ślaski Grzegorz, Klockiewicz Zbyszko

Archiwum Motoryzacji

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2022

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Vol. 96, nr 2

77--95

EN

The paper shortly presents shock absorber design evolution and resulting achieved characteristics. The way in which suspension performance is evaluated is described giving information about models used for suspension parameter tuning during simulation testing of suspension transmissibility (FRF - Frequency Response Function) for most important suspension assessment criteria. More detailed information about models of shock absorber (damper) nonlinearities of characteristics allows for description of methods of linear and nonlinear suspension models FRF estimation. Testing linear suspension model is possible with the use of analytical transfer function formulas which were used to verify methods for estimation FRF using estimated power spectral density functions of excitation and response signals. Designing appropriate input signal allowing to get useful response signals was necessary to for the success of this research. Proposed FRF estimation method was used for linear estimation of nonlinear suspension for a given range of working condition. It was demonstrated that there is no single value of a damping coefficient which would make the linear model responses similar to the responses of the nonlinear one. Then the bilinear model was proposed, giving good damper static nonlinear characteristic.

5

Forced response of plate with viscoelastic auxetic dampers

Stręk T.

Vibrations in Physical Systems

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2018

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Vol. 29

art. no. 2018003

EN

The example studies a forced response of plate with viscoelastic auxetic damper located at the free end of the plate. Damping elements consist of the cover layer and layer of viscoelastic material with positive or negative Poisson's ratio. Viscoelastic materials are often used for reduction of vibration (seismic or wind induced vibrations in building structures or other structures). The common feature is that the frequency of the forced vibrations is low. Calculations are made using finite element method with Comsol Multiphysics software.

6

Low-frequency pressure fluctuation damper based on hydropneumatic spring with constant stiffness

Figiel A., Kudźma Z., Stosiak M.

Journal of Theoretical and Applied Mechanics

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2018

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Vol. 56 nr 3

841—855

EN

A wide spectrum of pressure fluctuation frequencies occurs in hydraulic systems. Particularly hazardous and difficult to eliminate are pressure fluctuations in the range up to 50 Hz, resulting in the generation of infrasounds by machines equipped with a hydrostatic drive. The best protection against the harmful effect of ultrasounds is to suppress them at the very source, i.e. to eliminate the causes of the generation of this noise. This paper presents a concept of reducing pressure fluctuation in the range of low excitation frequencies by means of a low-frequency damper of special design. The basis for designing pressure fluctuation dampers effective in reducing pressure fluctuation amplitudes in the range of low frequencies (< 50 Hz), which also function as acoustic filters of the generated infrasounds, is provided. The effectiveness of the low-frequency damper in reducing pressure fluctuation amplitudes has been experimentally tested. The damper was found to be most effective when its eigenfrequency coincided with the excitation frequency to be reduced.

7

A method of vibration damping for diesel engine cylinder liners to prevent the consequences of erosion

Waliszyn A., Adamkiewicz A.

Eksploatacja i Niezawodność

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2018

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Vol. 20, no. 3

371--377

EN

This article presents the utilitarian need to determine the free vibrations of marine Diesel engine cylinder liners and the authors’ own studies in this area. Theoretical investigations on free vibrations and experimental ones on forced vibrations have been described. Theoretical studies have been conducted with the application of characteristic dimensionless numbers in the Elektroniks Workbench and Wis Sim digital environment enabling virtual modeling of cylinder liner vibrations and determination of their characteristics: amplitudes, frequencies and accelerations. In the theoretical examination mechanical and electrical system analogues have been applied. A calculation method for the cylinder liner vibration damper, developed as a result of the study, has been discussed. Electrical oscillation damping filter design methods basing on the Bessel, Batterword and Chebyshev polynomials have been used. The course of the experimental examinations has been described and their results have been presented. Validation of the developed method has been executed applying measurement results concerning the parameters of Diesel engine cylinder liner vibration with various elastic elements. The results of the authors’ own, theoretical and experimental, examinations have been confronted with those obtained by other scholars.

PL

W artykule uzasadniono potrzebę określenia drgań własnych tulei cylindrowych silników okrętowych o zapłonie samoczynnym. Opisano badania własne w tym zakresie: teoretyczne dotyczące drgań własnych i eksperymentalne, dotyczące drgań wymuszonych. W badaniach teoretycznych do modelowania zastosowano liczby kryterialne podobieństwa z wykorzystaniem środowiska cyfrowego Elektroniks Workbench i Wis Sim. Umożliwiły one modelowanie wirtualne drgań tulei cylindrowych i określenie ich charakterystyk: amplitudy, częstości i przyśpieszenia. W badanach tych zastosowano analogi układów mechanicznych i elektrycznych. Opracowano metodę tłumienia drgań tulei cylindrowych z zastosowaniem filtrów tłumienia drgań elektrycznych w oparciu o wielomiany Bessela, Batterworda i Czebyszewa. Opisano przebieg badań eksperymentalnych i pokazano otrzymane wyniki. Walidację opracowanej metody przeprowadzono wykorzystując wyniki pomiarów parametrów drgań tulei cylindrowej silnika spalinowego z różnymi elementami sprężystymi. Skonfrontowano wyniki badań własnych z wynikami badań innych badaczy.

8

Review of magnetorheological dampers

Skalski P., Ślubowska W.

Zeszyty Naukowe Instytutu Pojazdów / Politechnika Warszawska

|

2017

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z. 3/112

69--76

EN

In the paper the comprehensive review of the research and development done on different constructions of magnetorheological dampers. In the introduction part the magnetorheological materials are characterized and examples of magnetorheological dampers are presented. In the next part of this document the construction solutions of dampers with magnetorheological fluids are described. Then in the third Section the dampers with magnetorheological elastomers are shown. At the end, the conclusions are delivered.

PL

W niniejszej publikacji przedstawiony jest kompleksowy przegląd konstrukcji tłumików magnetoreologicznych. We wprowadzeniu scharakteryzowane są materiały magnetoreologiczne i przykłady tłumików magnetoreologicznych są przedstawione. W kolejnej części pracy prezentowane są rozwiązania konstrukcyjne tłumików z cieczą magnetoreologiczną. W części trzeciej tłumiki z elastomerami magnetoreologicznymi są pokazane. Praca kończy się konkluzjami.

9

Design and development of a semi-active suspension system for a quarter car model using PI controller

Siswoyo H., Mir-Nasiri N., Ali M. H.

Journal of Automation Mobile Robotics and Intelligent Systems

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2017

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Vol. 11, No. 4

26--33

EN

This paper presents the design and development of a semi-active suspension system for a vehicle. The main idea is to develop a system that is able to damp vibration of the vehicle body while crossing the bumps on the road. This system is modeled for a single wheel assembly and then the laboratory prototype of the complete system has been manufactured. It is used to physically simulate the spring-mass-damper system in vehicle and observe the frequency response to the external disturbances. The developed low-cost smart experimental equipment consists of a motor with offset mass which works as an oscillator to induce vibration, a spring-mass-damper system where the variable damper works as a pneumatic cylinder that allows varying the damping constant (c). Proportional-Integral (PI) controller is used to control the damping properties of the semi-active suspension system automatically. The system is designed in contrast to the most of the available suspension systems in the market that have only passive damping properties. The results of this research demonstrate the efficiency of the developed variable damper-based control system for the vehicle suspension system.

10

Stanowisko do określania właściwości lepko-sprężystych i dynamicznych charakterystyk elementów zawieszenia pojazdu

Błażejewski A., Głowiński S.

Autobusy : technika, eksploatacja, systemy transportowe

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2017

|

R. 18, nr 6

547--550, CD

PL

W artykule omówiony został problem badania właściwości lepko-sprężystych elementów zawieszenia pojazdów. Dobór właściwej charakterystyki zawieszenia pojazdu ma zasadnicze znaczenie, nie tylko dla komfortu jazdy, ale również dla bezpieczeństwa. Obecnie stosuje się coraz szerzej zawieszenia regulowane, gdzie sztywność elementów jest dobierana indywidualnie w zależności od warunków jazdy. Niezbędna jest więc znajomość właściwości tłumiących, lub inaczej lepko-sprężystych, poszczególnych elementów składowych zawieszenia. Jednym z rozwiązań stanowiska do wyznaczania tych właściwości, jest rozwiązanie przedstawione w tym artykule. Prezentowane stanowisko składa się z dwóch zasadniczych części: elektromechanicznej (napędowej) oraz pomiarowej (tory pomiarowe). Wykonano na stanowisku przykładowe badania i dokonano analizy przy wykorzystaniu środowiska obliczeniowo-analitycznego sygnałów otrzymanych z torów pomiarowych. W tym przypadku zastosowano oprogramowanie LabView oraz Matlab.

EN

In this paper results of tests of vertical dynamic wheel loads due to changes of suspension damping level are presented.This research allows to calculate a viscoelastic properties of suspension elements such as dampers and shock absorbers.These elements are essential for drivers comfort and moreover for their safety.At the test stand presented in this work, the changes of damping level were performed using semi-active shock absorbers.Article presents suspension goals, methods of test with information about used apparatus and sensors. At the end of article, the results in the form of characteristics, are presented and interpreted using LabView and Matlab software.

11

Role of magnetorheological fluids and elastomers in today’s world

Skalski A., Kalita K.

Acta Mechanica et Automatica

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2017

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Vol. 11, no. 4

267--274

EN

This paper explains the role of magnetorheological fluids and elastomers in today’s world. A review of applications of magnetorheological fluids and elastomers in devices and machines is presented. Magnetorheological fluids and elastomers belong to the smart materials family. Properties of magnetorheological fluids and elastomers can be controlled by a magnetic field. Compared with magnetorheological fluids, magnetorheological elastomers overcome the problems accompanying applications of MR fluids, such as sedimentation, sealing issues and environmental contamination. Magnetorheological fluids and elastomers, due to their ability of dampening vibrations in the presence of a controlled magnetic field, have great potential present and future applications in transport. Magnetorheological fluids are used e.g. dampers, shock absorbers, clutches and brakes. Magnetorheological dampers and magnetorheological shock absorbers are applied e.g. in damping control, in the operation of buildings and bridges, as well as in damping of high-tension wires. In the automotive industry, new solutions involving magnetorheological elastomer are increasingly patented e.g. adaptive system of energy absorption, system of magnetically dissociable [hooks/detents/grips], an vibration reduction system of the car’s drive shaft. The application of magnetorheological elastomer in the aviation structure is presented as well.

12

Hydropneumatyczne zawieszenie pojazdu gąsienicowego z amortyzacją cierną

Wocka P., Tomaszewski S.

Szybkobieżne Pojazdy Gąsienicowe

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2016

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nr 1 (39)

39--55

PL

W artykule przedstawiono koncepcje hydropneumatycznego zawieszenia pojazdu gąsienicowego opartego o zespół cylindra hydropneumatycznego i amortyzatora ciernego zintegrowanego z piast wahacza. Omówiono przeznaczenie, konfigurację , budowę pojedynczego zespołu zawieszenia oraz kinematykę i koncepcję budowy układu zawieszenia pojazdu gąsienicowego.

EN

The paper presents the concept of a hydropneumatic suspension of a tracked vehicle based on the hydropneumatic cylinder arrangement and friction damper integrated with the suspension arm holder. The purpose, configuration, design of single suspension unit and the kinematics and design concept of the suspension system of a tracked vehicle are discussed.

13

Hydropneumatic suspension of a tracked vehicle with friction dampers

Wocka P., Tomaszewski S.

Szybkobieżne Pojazdy Gąsienicowe

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2016

|

nr 1 (39)

147--162

EN

The paper presents the concept of a hydropneumatic suspension of a tracked vehicle based on the hydropneumatic cylinder arrangement and friction damper integrated with the suspension arm holder. The purpose, configuration, design of single suspension unit and the kinematics and design concept of the suspension system of a tracked vehicle are discussed.

14

Akumulator w układach hydraulicznych. Część II. Dobór i zastosowanie akumulatora

Oleksiuk M.

Napędy i Sterowanie

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2016

|

R. 18, nr 11

20--24

PL

To druga część publikacji dotyczącej akumulatorów. W tej części zamieszczono zasady doboru oraz opis zastosowania akumulatorów w układach hydraulicznych.

15

Akumulator w układach hydraulicznych. Część I. Funkcje i zjawiska w nim zachodzące

Oleksiuk M.

Napędy i Sterowanie

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2016

|

R. 18, nr 10

18--20

PL

Akumulator w układach hydraulicznych spełniać może wiele różnych, pożytecznych funkcji. Jego sensowne zastosowanie wymaga jednak znajomości jego cech, warunków pracy oraz ograniczeń. Niniejsza publikacja ma na celu przybliżenie powyższych aspektów. Ze względu na objętość publikacja podzielna została na dwie części. Poniżej prezentowana jest część I, opisująca podstawowe informacje o gazowych akumulatorach hydraulicznych.

16

Observations of MR fluid clumping behaviour in a squeeze-mode damper

Sapiński B.

Acta Mechanica et Automatica

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2016

|

Vol. 10, no. 3

239--245

EN

The study summarises the results of quasi-static experimental tests of an MR squeeze-mode damper prototype (MRSQD) performed at the MTS testing machine. Of particular interests was the influence of MR fluid clumping behaviour in the MRSQD working gap on the force output of the device. The MRSQD tests were assessed by measuring the damping force output at prescribed sinusoidal displacement inputs and at various (fixed) voltage levels resulting in the respective average current levels in the control coil. The influence of piston position offset on the damping force was also investigated. The collected data were shown in the form of damping force time histories and damping force-piston displacements loops and discussed with respect to MR fluid clumping behaviour.

17

Metodyka identyfikacji parametrów modelu lepkoplastycznego badanej cieczy magnetoreologicznej

Skalski P.

Logistyka

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2015

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nr 3

4392--4397, CD 1

PL

Głównym celem pracy jest metodyka identyfikacji parametrów prawa Perzyny dla cieczy magnetoreologicznej. Estymowany model został zastosowany do symulacji numerycznych, która pozwoliła na opis zachowania cieczy magnetoreologicznej w szczelinie pracującego urządzenia. Porównane wyniki symulacji numerycznych i z danymi eksperymentalnymi potwierdzają metodę identyfikacji parametrów modelu lepkoplastycznego dla badanej cieczy MR.

EN

The main aim of this work is the parameters identificaton methodology of the Perzyna model for magnetorheological fluid. Identified model was used to develop the simulations that verifie the proposed mathematical model which describes the behaviour of an MR fluid in the operating gap of a machine’s head, with data derived from performed experiments.

18

Analiza właściwości cieczy magnetoreologicznej na podstawie danych eksperymentalnych

Skalski P.

Logistyka

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2015

|

nr 3

4382--4391, CD 1

PL

Głównym celem pracy jest analiza właściwości cieczy magnetoreologicznej w eksploatacyjnych warunkach pracy amortyzatora, zrealizowana na podstawie danych eksperymentalnych. Zakres badań został ograniczony do amortyzatora LORD RD 1005-3. Na podstawie wykonanych eksperymentów, wyznaczono m.in. umowną granicę plastyczności oraz maksymalne naprężenia ścinające analizowanej cieczy MR, z uwzględnieniem zmiennej prędkości ścinania, natężenia prądu elektrycznego płynącego w solenoidzie. Przeprowadzona analiza właściwości cieczy MR może zostać wykorzystana w estymacji parametrów modeli lepkoplastycznych.

EN

The main aim of this work is an analysis of properties of a magnetorheological fluid, in operational conditions of a damper’s work. The scope of research has been limited to one device: LORD RD 1005-3 shock absorber. On the basis of performer experiments, it has been estimated i.e.: the conventional yield point and the maximum shear stress of analyzed MR fluid, including variable shear rate, intensity of current flowing in a solenoid. The analysis of MR fluid properties can be used in the estimation of parameters of the viscoplastic models.

19

Refined model of passive branch damper of pressure fluctuations

Kudźma S., Kudźma Z.

Journal of Theoretical and Applied Mechanics

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2015

|

Vol. 53 nr 3

557--567

EN

This paper presents an analysis of the influence of the kind of a friction model on the dimensioning of a branch pressure fluctuation damper. The mathematical model of the branch damper is defined by determining the damper input impedance and finding its minimum corresponding to the maximum effectiveness in reducing pressure fluctuations. Three kinds of friction for the oscillatory flow in the damper, i.e. a lossless line, steady friction and a nonstationary friction model, are considered. Experimental studies confirmed that the use of the nonstationary friction model in the calculation of branch damper length ensures the highest effectiveness in reducing the amplitude of pressure fluctuations characterized by a given frequency.

20

Role of selection of measuring methods in diagnosing of structure actual surface in the rubbery torsional vibration dampers

Ciecińska B., Homik W.

Diagnostyka

|

2015

|

Vol. 16, No. 2

55--60

EN

The paper presents problem of selecting the measuring method of geometric structure of the surface formed by laser beam in damper. Measurements in 2D system, in the context of value and giving satisfactory results need to be verified in 3D. This is due to the fact, that the surface after the laser machining is specific. Although, you can choose the machining options that allow to obtain a certain roughness of the surface, but there is no information about its spatial structure. Such information includes a description of the structure made in 3D system.

PL

W pracy przedstawiono problem doboru metody pomiaru struktury geometrycznej powierzchni tworzonej wiązką lasera na powierzchniach czynnych tłumikach. Pomiary w układzie 2D, dające w kontekście wartości satysfakcjonujące rezultaty wymagają weryfikacji w układzie 3D. Jest to spowodowane tym, że powierzchnia po obróbce laserowej jest specyficzna. Można wprawdzie wybrać te warianty obróbki, które umożliwiają uzyskanie określonej chropowatości powierzchni, ale brak jest informacji o jej strukturze przestrzennej. Takie informacje zawiera opis struktury wykonany w układzie 3D.