BazTech - Yadda

1

Structural tests of freight wagons on the basis of signals generated by piezoelectric macro fiber composites

Płaczek M., Wróbel A., Buchacz A.

Acta Mechanica et Automatica

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2017

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Vol. 11, no. 3

210--216

EN

Paper presents a report of a research work that concerns possibilities of freight wagons modernization using new composite materials. The main aim of presented work was to verify the possibility of inference from the dynamic response of the wagon about the changes in its technical condition. During the presented works tests on real objects were carried out using Macro Fiber Composite (MFC) piezoelectric transducers glued to the freight wagon’s frame. The dynamical response of the wagon was measured while the object was driving. On the next stage the measured signal was generated on a laboratory stand using electrodynamic modal shaker and vibrations of the laboratory model were measured. Measured signals were juxtaposed on charts and analysed. The aim of this work was to verify if it is possible to detect the change in the system using measurements of vibrations that are being generated during exploitation of the freight wagon.

2

Experimental and numerical analysis of guided waves propagation in narrow isotropic plate with notch

Barski M., Pająk P.

Journal of KONES

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2014

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Vol. 21, No. 1

23--30

EN

The phenomenon of the guided waves propagation can be applied in order to detect different types of damages in real structures. The existence of flaws, like cracks, notches, or holes, causes the change of the wave propagation in the analysed structure in comparison with the intact one. However, in the vicinity of the free edges the dynamic response is very complicated due to the reflections and interference of the incident waves. Thus, the process of the damage detection and localization can be very difficult. Therefore, the current work is devoted to the experimental and numerical analysis of the guided waves propagation in the narrow, thin plates (beams). The investigated structure is made of aluminum alloy. Mainly, the influence of the notch on the waves’ propagation is studied. The waves are generated and picked up by the piezoelectric transducers. In order to carry out the numerical simulations the finite element method is applied. Moreover, the piezoelectric activators and sensors are modelled with the use of the coupled field finite solid elements and the plate with the use of the structural solid elements. Generally, three types of the waves are observed, namely the horizontal and shear wave, which move along the symmetry axis of the plate and the horizontal wave, which propagates in the perpendicular direction. The existence of the notch generally causes that the voltage amplitude of the received signal is reduced in comparison with the results obtained for the intact structure. Qualitatively, the similar effect is observed in the case of the experimental findings.

3

Modelling of passive vibration damping using piezoelectric transducers – the mathematical model

Buchacz A., Płaczek M., Wróbel A.

Eksploatacja i Niezawodność

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2014

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Vol. 16, no. 2

301--306

PL

W pracy przedstawiono propozycję modelowania matematycznego drgających przetworników piezoelektrycznych poprzez zastosowanie analogii elektrycznej. Opracowany model stosowany jest w analizie oraz wyznaczaniu charakterystyk drgających płytek piezoelektrycznych z dołączonymi, zewnętrznymi, biernymi elementami elektrycznymi. Wprowadzono układ zastępczy przetwornika piezoelektrycznego równoważny trójwrotnikowi elektrycznemu. W pracy analizowano połączenia dwóch płytek piezoelektrycznych działających jako transformator piezoelektryczny, wprowadzając układy zastępcze obu przetworników. Przy stosowaniu układów zastępczych w postaci obwodów elektrycznych wszystkie wielkości mechaniczne w otrzymanym układzie Masona zostały zastąpione równoważnymi wielkościami elektrycznymi.

EN

A proposal of mathematical modelling of vibrating piezoelectric transducers using the electrical analogy is presented in this work. The developed mathematical model is used in analysis of vibrating piezoelectric plates with adjoined external passive electric elements and for designating of their characteristics. A substitute electric system of the piezoelectric transducer that is equal to a three-port system was introduced. A piezoelectric transformer created by connection of two plates was analysed. Substitute systems of both plates were introduced. All mechanical parameters of the analysed system were replaced by equivalent electrical parameters in obtained Mason’s model.

4

Numerical Investigation of Piezoelectric Element Coupling Degradation in Active Beam Systems

Freundlich J. K., Pietrzakowski M.

Machine Dynamics Research

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2013

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Vol. 37, No. 4

13-26

EN

The objective of the present study is to develop modelling of the piezoelectric element edge delamination process and analysis of effects of the progressive adhesive interlayer damage on active beam dynamic behaviour. In the considered system piezoelectric patches are mounted to both opposite sides of the beam and operate as a collocated sensor/actuator pair with velocity feedback. Herein, the actuator coupling damage is described as a large reduction of the adhesive interlayer shear stiffness. It is assumed that the damaged zone of the decreased stiffness extends uniformly across the actuator from its edges to the centre. In the analysis, the beam is divided into sections due to its geometry and the supposed delaminated regions. The calculations are performed using the FE analysis. In the first step, the cantilever beam with piezoelectric elements bonded to the beam surface by a thin glue layer of uniform properties is analysed. The beam is excited by a time varying force. In order to validate the arranged FE model, the analytical and FE calculations of open and closed loop dynamic responses are performed. The compared results show quite good agreement and prove that the applied FE model of the considered system is correct and can be accepted for further numerical analysis. In the next step, FE simulations of the beam forced vibration suppressed by piezoelectric control system with velocity feedback are accomplished. The influence of the length of damaged zone on the dynamic characteristics and the control effectiveness is investigated. As expected, the size, type and location of the coupling damage influence on the dynamic characteristics of the examined beam and cause reduction of the system control efficiency.

5

Indication of the suitable model of a mechatronic system as an introduction to the synthesis task

Płaczek M.

Journal of Achievements in Materials and Manufacturing Engineering

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2011

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Vol. 49, nr 2

338--349

EN

Purpose: The identification of the optimal mathematical model that meets the assumed criteria is the main purpose of this paper, which is an introduction to the task of synthesis of one-dimensional vibrating mechatronic systems. Assumed criteria are to provide the accurate analysis of the system together with maximum simplification of used mathematical tools and minimize required amount of time. The correct description of a given system by its model during the design phase is a fundamental condition for proper operation of it. Therefore, the processes of modelling, testing and verification of used models were presented. On the basis of carry out analysis the optimal (in case of assumed criteria) model was selected and it will be used to realize the task of synthesis in future works. Design/methodology/approach: A series of mathematical models with different simplifying assumptions was created. Using the created models and corrected approximate Galerkin method the dynamic characteristic of the considered system was designated. The analysis of an influence of parameters of the system’s components on obtained characteristic was conducted. The approximate method was verified to check its accuracy and decide if it can be used to analyse such kind of mechatronic systems. Findings: The main result of the work is an indication of the suitable mathematical model of the considered system. Research limitations/implications: Influence of temperature changes on the transducer’s properties was neglected in developed mathematical models. It will be considered in the future works. Practical implications: Presented method of mechatronic system’s analysis can be use in process of designing of technical devices where both, simply and reverse piezoelectric effects can be used. Originality/value: Development of the mathematical models in which the considered system is modelled as a combined beam.

6

Modelowanie MES konstrukcji inteligentnych

Ścisło Ł.

Czasopismo Techniczne. Mechanika

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2011

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R. 108, z. 3-M

113-121

PL

W dzisiejszych czasach dużą rolę w systemach tłumienia drgań ma klasa materiałów o własnościach adaptacyjnych w literaturze określanych jako materiały inteligentne. Do jednych z najbardziej popularnych należą elementy piezoelektryczne (PZT), które mogą być stosowane m.in. w systemach redukcji drgań i hałasu. Celem artykułu jest przedstawienie niektórych z możliwych analiz numerycznych inteligentnej belki, przy zastosowaniu metody elementów skończonych (MES) w programie ANSYS. Przedstawione zostaną trzy przykładowe analizy: modalna, harmoniczna oraz analiza dynamiczna stanów przejściowych. Szczególna uwaga poświecona będzie dynamicznej analizie transientowej, która umożliwia implementacje i dalszy rozwój systemu kontroli przy użyciu parametrycznego języka programowania programu ANSYS (ADPL). Udowodnione zostanie, iż możliwe jest stworzenie poprawnie działającego modelu, który w przyszłości posłuży do wyboru najodpowiedniejszej metody sterowania, która zostanie także przetestowana na stanowisku laboratoryjnym.

EN

Development in materials engineering effected in discovery of new materials which have adaptive properties. One of the most popular ones are piezoelectric elements (PZT) which may be implemented in vibration control systems. The paper presents some of the possible analyses of a smart beam which exist in the laboratory carried out using finite element method (FEM) in ANSYS. Three of the particular analyses will be presented: modal analyses, harmonic analyses and transient analyses. Special attention will be given to transient dynamic analyses which allows implementation and development of a control system using ANSYS Parametric Design Language (APDL).

7

Analiza stanu przejściowego drgań belki z elementami piezoelektrycznymi metodą elementów skończonych

Kozień M., Ścisło Ł.

Czasopismo Techniczne. Mechanika

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2011

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R. 108, z. 1-M

75-81

PL

Zastosowanie sterowanych elementów piezoelektrycznych, rozmieszczonych w odpowiedniej konfiguracji na powierzchni drgającej belki jest jedną ze współcześnie rozwijanych metod redukcji ich drgań. Jednym z istotnych zagadnień jest tłumienie wielomodalne. Elementy piezoelektryczne - aktuatory - powinny być rozmieszczone na powierzchniach zewnętrznych w taki sposób, aby leżały w obszarach o dużej krzywiźnie wynikającej z postaci drgań. Możliwe są dwie podstawowe realizacje układu: pasywny bez sterowania, dobrany na określone częstotliwości, lub aktywny ze sterowaniem. Celem pracy było zbudowanie i przetestowanie kodu pozwalającego na analizę stanu przejściowego drgań wymuszonych belki. Uzyskane rezultaty analiz pokazują, ze możliwy staje się zapis algorytmu sterowania w języku APDL pakietu metody elementów skończonych Ansys.

EN

Application of the controlled piezoelectric elements, suitable distributed over the external surfaces of the vibrating beam is one of the contemporary applied method of reduction of its vibrations. One of the important problems is the multimodal damping. The piezoelectric elements - actuators - should be distributed on the external surfaces in areas of high curvatures comminf from the vibrations shapes. Two basic attemps of damping can be applied: active one with control system or and passive one designed for chosen frequency. The aim of the paper was to built and to test tke numerical code for transient analysis of excited and active damped beam. The obtained results makes possible to do the next step: to write the APDL control procedure in the Ansys finite element method system.

8

Sterowalne materiały inteligentne w budownictwie

Ścisło Ł.

Czasopismo Techniczne. Budownictwo

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2011

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R. 108, z. 1-B

163-171

PL

Dzięki rozwojowi techniki i materiałoznawstwa coraz więcej nowych materiałów znajduje zastosowanie w wielu dziedzinach techniki, w tym także w budownictwie. Jedną z ciekawszych możliwości wartych bacznej uwagi może być pewna klasa materiałów, w bibliografii określana jako materiały inteligentne (smart materials, inteligent materials). Konstrukcje inteligentne znalazły szczególne zastosowanie tam, gdzie wymagane jest szybkie i skuteczne tłumienie dźwięków i wibracji. Jednym z głównych zagadnień artykułu jest pokazanie kilku możliwych rozwiązań aplikacyjnych wykorzystujących materiały inteligentne w budownictwie. Przedstawiony zostanie przegląd literatury i zastosowań oraz pokazane zastaną przykładowe aplikacje autora. Szczególna uwaga zostanie skupiona na cieczy magneto-reologicznej (MR) oraz przetwornikach piezoelektrycznych (PZT) jako klasie materiałów mogących mieć szerokie zastosowanie we współczesnym budownictwie, zwłaszcza w budowie konstrukcji mostowych. Zaprezentowane zostanie także wykorzystanie tłumika MR w celu tłumienia drgań długich lin mostów podwieszanych oraz zastosowanie przetworników piezoelektrycznych wykorzystywanych do tłumienia drgań i dźwięków wytworzonych przez wibrującą strukturę płytowo-belkową, taką, jaka występuje w przypadku mostów kratownicowych.

EN

Due to development of modern technologies and material science more new materials can be implemented in many different fields, including civil engineering. One of the most interesting possibilities is the use of the special class of materials which in literature are being referred to as smart or intelligent materials. Intelligent structures can be especially used in cases where fast and efficient way of damping sounds and vibrations is required. The focus of the paper is to show a few possible implementations in civil engineering where smart materials may be used. The current research will be presented as well as two of the possible implementations developed by the author. Two types of the controllable materials will be presented, magnetorheological fluid (MR) used in MR damper and piezoelectric transducers (PZT) used in vibrations suppression systems, as the classes of materials which can be used in many applications in modern civil engineering- especially in bridges structures. The application where MR dumper is being used for vibration mitigation system for long lines of cable stayed-bridges will be shown as well as application where the system of piezoelectric transducers is used for damping sounds and vibrations of plate and beam structures. Such structures are used for plate girder or truss bridges.

9

Ferroelectric and ferroelectromagnetic ceramics in a view of possibilities to be used in electroacoustic

Czerwiec M., Zachariasz R., Brzezińska D., Ilczuk J.

Hydroacoustics

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2008

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Vol. 11

63-70

EN

Ferroelectric ceramics were born in the early 1940's with the discovery of the phenomenon of ferroelectricity as the source of the unusually high dielectric constant in ceramic barium titanate capacitors. Since that time, they have been the heart and soul several multibillion dollar industries, ranging from high-dielectric-constant capacitors to later developments in piezoelectric transducers, positive temperature coefficient devices, and electrooptic light valves. Various ceramic formulations, their form, fabrications, functions, and future are described in relation to their ferroelectric nature and specific areas of applications. This paper is intended to illustrate practical uses of ferroelectric and ferroelectromagnetic ceramics obtained and investigated by the authors.

10

Multicomponent ceramic materials on the basis of PZT for the production of piezoelectric resonators

Bochenek D., Surowiak Z., Gavrilyachenko S. V., Kupriyanov M. F.

Archives of Acoustics

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2005

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Vol. 30, No. 1

87-107

EN

Investigations on the influence of the PbTiO3 content on the crystalline and domain structure of PZT-based four-component solid solutions have been performed. It has been shown that there is a close relation between the structure and temperature stability of the resonance frequency (fr) of the fabricated piezoceramic transducers. Better and more stable results have been obtained by doping and modifying the basic chemical composition obtaining Pb(Zr1-x Tix)O3. The compositions with minimal Δ fr / fr, within the temperature range T = 213–358 K (in relation to room temperature Tr = 293 K), exhibited (i) the smallest internal friction (Q-1m), (ii) the highest mechanical quality (Qm), (iii) high values of spontaneous deformation of the elementary cell (δT and δRe), (iv) the complex a-c-domain structure in the tetragonal phase (T) and the simple domain structure in the rhombohedral phase (Re). The practical result of the present work was the fabrication of piezoceramic electric band filters exhibiting Δ fr / fr < 0.2% and a high mechanical quality factor (Qm = 3225).