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1

Experimental of buckling restrained brace hysteretic performance with carbon fiber wrapped in concrete

Fang Yuan, Lv Lei, Gao Yuqiang, Fu Zhongqiu

Archives of Civil Engineering

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2024

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Vol. 70, nr 1

527--541

EN

Buckling restrained brace is an important structure for improving the seismic resistance of structures. Conducting research on new types of buckling restrained brace can improve the seismic performance and reliability of buckling resistant support. Four different types of buckling restrained braces specimens were designed and manufactured: cross-shaped square steel pipe members, cross-shaped round steel pipe members, cross-shaped carbon fiber members, and in-line carbon fiber members. By conducting quasi-static tests, the force displacement hysteresis curves, skeleton curves, stiffness degradation, equivalent viscous damping coefficient, and energy dissipation ratio of four different types of buckling restrained brace were analyzed. The research results showed that all four buckling restrained brace specimens have good hysteresis performance. The load-bearing capacity and energy consumption performance of the three specimens of square steel pipe, round steel pipe and carbon fiber with the same core unit are the same, but the inline type is worse than the cross type. The core unit specimen with a width of 80 mm is about 60% higher in bearing capacity and energy consumption than a specimen with a width of 50 mm. The core unit of some specimens undergoes multi-wave buckling. For carbon fiber specimens, the CFRP is prone to breakage due to the lateral thrust of the restraining unit. Therefore, steel hoop or stirrup should be added to the end to improve the restraint effect when designing and manufacturing.

2

Nonsmooth optimization control based on a sandwich model with hysteresis for piezo-positioning systems

Yang Sen, Tan Yonghong, Dong Ruili, Tan Qingyuan

International Journal of Applied Mathematics and Computer Science

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2023

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Vol. 33, no. 3

449--461

EN

A nonsmooth optimization control (NOC) based on a sandwich model with hysteresis is proposed to control a micropositioning system (MPS) with a piezoelectric actuator (PEA). In this control scheme, the hysteresis phenomenon inherent in the PEA is described by a Duhem submodel embedded between two linear dynamic submodels that describe the behavior of the drive amplifier and the flexible hinge with load, respectively, thus constituting a sandwich model with hysteresis. Based on this model, a nonsmooth predictor for sandwich systems with hysteresis is constructed. To avoid the complicated online search for the optimal value of the generalized gradient at a nonsmooth point, the method of the so-called weighted estimation of generalized gradient is proposed. In order to compensate for the model error caused by model uncertainty, a model error compensator (MEC) is integrated into the online optimization control strategy. Afterwards, the stability of the control system is analyzed based on Lyapunov’s theory. Finally, the proposed NOC-MEC method is verified on an MPS with a PEA, and the corresponding experimental results are presented.

3

Zmodyfikowana metoda balistyczna do wyznaczania charakterystyki magnesowania

Pilśniak Adam, Pasko Szymon, Zackiewicz Przemysław, Kolano-Burian Aleksandra

Przegląd Elektrotechniczny

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2022

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R. 98, nr 11

201--204

PL

Pomiar charakterystyk magnesowania można zrealizować na kilka sposobów. Jednym z nich jest metoda balistyczna (komutacyjna), która ze względów technicznych została zaniechana w ostatnich latach. Pojawiające się nowe możliwości techniczne, tj. klucze energoelektroniczne, przetworniki AC z krótkim czasem próbkowania, umożliwiły modyfikację znanej metody pomiarowej. Przedstawiono teoretyczne i praktyczne różnice w pomiarze krzywych magnesowania za pomocą popularnej metody transformatorowej, jak i nowej metodzie komutacyjnej.

EN

There are a number of ways to measure the parameters of the magnetic cores. One of them is the ballistic (commutation) method, which was rarely used for technical reasons In recent years. New technical possibilities, i.e. fast DAC and power electronic devices made it possible to create new measuring systems operating on the basis of the already known methods. Theoretical and practical differences of magnetization curves and parameters of the cores obtained by the AC and DC methods are presented.

4

Improvement of the model of an asynchronous traction motor of an electric locomotive by taking into account power losses

Goolak Sergey, Riabov Ievgen, Gorobchenko Oleksandr, Yurchenko Viktor, Nezlina Olena

Przegląd Elektrotechniczny

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2022

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R. 98, nr 5

1--10

EN

The paper proposes an improved model of an asynchronous traction motor, taking into account magnetic losses in the steel of the motor, as a function of time, based on the equations of specific losses. When conducting research, a mathematical model of an asynchronous motor, made in the MATLab software environment, was used. Based on the simulation results, the value of average magnetic losses and time diagrams of magnetic losses were obtained for the nominal operating mode of the motor. The results obtained are compared with the passport data of the motor.

PL

W pracy zaproponowano udoskonalony model asynchronicznego silnika trakcyjnego uwzględniający straty magnetyczne w stali silnikowej w funkcji czasu, oparty na równaniach strat właściwych. W badaniach wykorzystano model matematyczny silnika indukcyjnego, wykonany w środowisku oprogramowania MATLab. Na podstawie wyników symulacji uzyskuje się wartości średnich strat magnetycznych oraz wykresy czasowe strat magnetycznych dla nominalnego trybu pracy silnika, a uzyskane wyniki porównuje się z danymi paszportowymi silnika.

5

Układ i program do badania charakterystyki magnetycznej i stratności blach (SST-H)

Lerch Tomasz, Rad Michał, Rams Witold

Napędy i Sterowanie

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2022

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R. 24, nr 6

52--55

PL

Artykuł opisuje zbudowany i przetestowany układ do pomiarów charakterystyki magnetycznej i stratności blach elektrotechnicznych. Przedstawione zostały aspekty stosowania i cechy prezentowanego układu. Opisano również nowatorski algorytm ustalania kształtu napięcia zasilania tak, aby napięcie indukowane w cewce pomiarowej miało kształt sinusoidalny, czego wymagają normy. Przedstawione zostały również przykładowe wyniki pomiarów.

EN

The article describes a system for measuring magnetic characteristics and losses of core sheets used in electrical machines. Aspects of application and features of the presented system were presented. Standards requires that voltage waveform on the measuring coil during the test must be sinusoidal. An innovative algorithm for determining the shape of the supply voltage to fulfill this requirements is presented. Sample measurement results were also presented.

6

Impact of lift-off in 3MA-NDT harmonic analysis signal-via numerical methods and experiment

Amrane Cylia, Mimoune Souri Mohamed, Khene Mohamed Lotfi, Gabi Yasmine, Mohellebi Hassane, Alloui Lotfi, Straß Benjamin, Wolter Bernd

Przegląd Elektrotechniczny

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2021

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R. 97, nr 12

45--50

EN

In this paper, the impact of lift-off on the 3MA minaturized probe head via harmonic analysis method is discussed. The electromagnetic signals are examined using two numerical computational methods; the finite element method (FEM) and the finite volume method (FVM) by taking into account the hysteretic and eddy current behavior of ferromagnetic parts. The investigation is run on bilayer specimen and the result demonstrates the ability and accuracy of both FVM and FEM to reprocduce the experimental signals. Beside this, simulations are carried out for various lift-off in order to evaluate the skin depth and limit of the magnetic NDT technique.

PL

W artykule omówiono wpływ oderwania na głowicę sondy zminaturyzowanej 3MA metodą analizy harmonicznej. Sygnały elektromagnetyczne są badane za pomocą dwóch numerycznych metod obliczeniowych; metoda elementów skończonych (MES) i metoda objętości skończonych (FVM) z uwzględnieniem histerezy i zachowania prądów wirowych elementów ferromagnetycznych. Badanie prowadzone jest na próbce dwuwarstwowej, a wynik wykazuje zdolność i dokładność zarówno FVM, jak i MES do odtworzenia sygnałów doświadczalnych. Oprócz tego przeprowadzane są symulacje dla różnych podniesień w celu oceny głębokości skóry i granic magnetycznej techniki NDT.

7

An improved stress-dependent model for magnetomechanical effect simulation of Terfenol-D rods

Nait Ouslimane Ahmed, Mohellebi Hassane, Phan Quang Anh

Przegląd Elektrotechniczny

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2021

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R. 97, nr 1

115--120

EN

Terfenol-D is one of the smart materials widely used in the fabrication of magnetostriction based sensors and actuators due to its high material properties. However, using Terfenol-D in industrial applications rely on the ability of predicting its hysteresis by mathematical models. In this paper, we present an improved hysteresis model for reproducing hysteresis curves of Terfenol-D. Levenberg–Marquardt algorithm is used to estimate the optimal parameters of the improved model. The simulation and experimental results show the performances of the proposed model.

XX

Artykuł zajmuje się Terfenolem-D – dość powszechnie stosowanym materiałem magnetostrykcyjnym. Niestety dotychczas brakowało matematycznego modelu tego materiału uwzględniającego histerezę. Wykorzystano algorytm Levenberg–Marquardt do bardziej szczegółowego opisu parametrów Terfenolu.

8

Układ i program do badania charakterystyki magnetycznej i stratności blach (SST-H)

Lerch Tomasz, Rad Michał, Rams Witold

Maszyny Elektryczne : zeszyty problemowe

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2021

|

Nr 1 (125)

117--120

PL

Artykuł opisuje zbudowany i przetestowany układ do pomiarów charakterystyki magnetycznej i stratności blach elektrotechnicznych. Przedstawione zostały aspekty stosowania i cechy prezentowanego układu. Opisano również nowatorski algorytm ustalania kształtu napięcia zasilania tak, aby napięcie indukowane w cewce pomiarowej miało kształt sinusoidalny, czego wymagają normy. Przedstawione zostały również przykładowe wyniki pomiarów.

EN

The article describes a system for measuring magnetic characteristics and losses of core sheets used in electrical machines. Aspects of application and features of the presented system were presented. Standards requires that voltage waveform on the measuring coil during the test must be sinusoidal. An innovative algorithm for determining the shape of the supply voltage to fulfill this requirements is presented. Sample measurement results were also presented.

9

Determination of the difference between two complex polymer models simulating the behaviour of biological structures

Kmiecik Barbara, Labowska Magdalena, Detyna Jerzy

Biocybernetics and Biomedical Engineering

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2019

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Vol. 39, no. 2

503--511

EN

This article presents research conducted on various polymer models imitating biological structures. Tests were conducted using a newly developed research method described in [1]. The purpose of our research was to check if the measuring system [1] is able to distinguish multilayer samples. Test materials were two different polymer models which were subjected to pressure in the central point. Marked points on the external surface of the sample were followed during the measurement. The arrangement of points on the image allowed to reconstruct the 3D surface of the sample and to determine the displacement of the analysed points. Measurements were repeated 10 times to ensure the representativeness (credibility) of the conducted research. Statistical tests and artificial neural networks (ANN) were used to classify the examined samples. We used 5-fold cross-validation for training and validating the ANN. The entire set of 75 cases was divided into 5 equinumerous subsets. The obtained results suggest that the proposed method distinguished between the tested samples on the basis of results. Analysed materials react differently to the given mechanical factor.

10

Hysteretic behaviour model of soils under cyclic loads

Galindo Rubén, Patiño Hernán, Melentijevic Svetlana

Acta Geophysica

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2019

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Vol. 67, no. 4

1039--1058

EN

The article reports the application of the mathematical theory of hysteresis to soil dynamics to characterise its behaviour under the action of cyclic loads. Based on appropriate laboratory experiments for a given soil, the achieved values were verified in simulations. The cycle shapes of stress–strain shear response for all strain levels and different combinations of static and cyclic shear stress loading were replicated. For proper characterisation in the case of repeated loads, the model incorporates the phenomenon of degradation of the structure and generation of excess pore pressure in considering its continuous variation throughout the loading process using an energy approach. The model is defined by parameters with physical interpretations that are evident from the tests.

11

Wpływ zastosowania różnego rodzaju osnowy w materiałach kompozytowych na ich właściwości magnetyczne

Jakubas A., Dąbrowski R.

Zeszyty Naukowe Wydziału Elektrotechniki i Automatyki Politechniki Gdańskiej

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2018

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Nr 59

65--68

PL

W pracy przeprowadzono analizę wpływu materiału osnowy na właściwości magnetyczne miękkich materiałów kompozytowych (SMC). Badania przeprowadzono na próbkach rdzeni cylindrycznych wykonanych przez autorów z mieszaniny proszku żelaza i różnego rodzaju osnowy. Badania obejmowały wyznaczenie takich parametrów jak indukcja nasycenia Bs, natężenie koercji Hc i stratność. Pomiary wykonano przy różnej częstotliwości wymuszenia.

EN

Soft magnetic composites are often used in the design of electromagnetic converters and electrical machines. Their popularity is due to the ease of molding and the ability to adapt to specific applications. The paper presents magnetic properties of cores made of iron powder and different type of binder. Samples were prepared by compression in temperature dependent from binder / Fe powder mix. Measurement of magnetic parameters revealed an change in magnetic properties with using various types of binders. The presented measurement data show that it is possible to produce of SMC cores with good magnetic properties, using readily available components and in uncomplicated production processes. Cylindrical cores were made with different types of binders, respectively: powder of suspense polyvinyl chloride, powder of polytetrafluoroethylene, powder of polyethylene wax and transformer oil. For the prepared samples we have determined their basic magnetic properties. The analysis of collected measurement data showed a significant relationship between SMC sample forming parameters and their magnetic properties. In addition, the measurements showed a poor dependence of the magnetic properties in developed SMC samples on the excitation frequency. The method of producing a polymer-metal composite described in the article is the subject of patent application P.420850.

12

Investigation of the memristor nonlinear properties

Khrapko S., Rusyn V., Politansky L.

Informatyka, Automatyka, Pomiary w Gospodarce i Ochronie Środowiska

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2018

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T. 8, nr 1

12--15

EN

The study of nonlinear systems is an important research topic for scientists and researchers. Memristor, for a long time, it remained just as a theoretical element and rarely appeared in the literature because of having no simple and practical realization. In this paper, we reviewed the theoretical substantiation of the memristor and conducted a practical study of its nonlinear properties using the memristor company KNOWM of series BS-AF-W 16DIP. We also investigated the characteristics of the memristor via the LabView environment.

PL

Badanie systemów nieliniowych jest ważnym tematem dla badaczy i naukowców. Memrystor przez długi czas pozostawał elementem teoretycznym i rzadko pojawiał się w literaturze z powodu braku prostej i praktycznej realizacji. W tym artykule zostały przedstawione teoretyczne uzasadnienie memrystora i badania jego właściwości nieliniowych na przykładzie memrystora firmy KNOWM serii BS-AF-W 16DIP. Zostały przeprowadzone badania charakterystyk memrystora w środowisku LabView.

13

Applying a fractional coil model for power system ferroresonance analysis

Majka Ł.

Bulletin of the Polish Academy of Sciences. Technical Sciences

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2018

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Vol. 66, nr 4

467--474

EN

This paper addresses the problem of modeling the nonlinear coil used for ferroresonant circuit analysis. The effect of ferroresonance is described and a general modeling approach is presented. The hysteresis modeling problem is also shortly discussed, on the example of a ferromagnetic coil. A brief overview of available literature and contributors to this area are provided. A series RLC circuit supplied from an AC source is discussed. The application of the fractional derivative in the modeling of an iron core coil is presented and suggestions of model implementations are given. The computations performed are illustrated by means of waveform data obtained from computer simulations and compared with those obtained from measurements performed in a specially prepared laboratory setup.

14

Open loop control of piezoelectric tube transducer

Stefanski F., Minorowicz B.

Archives of Mechanical Technology and Materials

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2018

|

Vol. 38

23--28

EN

This paper is focused on the open loop control of a piezoelectric tube actuator, hindered by a strong hysteresis. The actuator was distinguished with 22 % hysteresis, which hinders the positioning of piezoelectric actuator. One of the possible ways to solve this problem is application of an accurate analytical inversed model of the hysteresis in the control loop. In this paper generalized Prandtl-Ishlinskii model was used for both modeling and open loop control of the piezoelectric actuator. Achieved modeling error does not exceed max. 2.34 % of the whole range of tube deflection. Finally, the inverse hysteresis model was applied to the control line of the tube. For the same input signal (damped sine 0.2 Hz) as for the model estimation the positioning error was max. 4.6 % of the tube deflection. Additionally, for a verification reason three different complex harmonic functions were applied. For the verification functions, still a good positioning was obtained with positioning error of max. 4.56 %, 6.75 % and 5.6% of the tube deflection.

15

Adsorption and Co-Adsorption of Polyaldehyde Dextran Nanoparticles and Nonionic Surfactant at an Air–Water Interface: Potential Implications for Pulmonary Drug Delivery

Jabłczyńska K., Sosnowski T. R.

Chemical and Process Engineering

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2017

|

Vol. 38, nr 1

67--77

EN

Measurements of dynamic surface tension were carried out in aqueous systems (water or 0.1 mM Triton X-100) comprising nanoparticles formed from chemically modified polyaldehyde dextran (PAD). The nanostructures, considered as potential drug carriers in aerosol therapy, were obtained from biocompatible polysaccharides by successive oxidation and reactive coiling in an aqueous solution. The dynamic surface tension of the samples was determined by the maximum bubble pressure (MBP) method and by the axisymmetric drop shape analysis (ADSA). Experiments with harmonic area perturbations were also carried out in order to determine surface dilatational viscoelasticity. PAD showed a remarkable surface activity. Ward-Tordai equation was used to determine the equilibrium surface tension and diffusion coefficient of PAD nanoparticles (D = 2.3×10-6 m2/s). In a mixture with Triton X-100, PAD particles showed co-adsorption and synergic effect in surface tension reduction at short times (below 10 s). Tested nanoparticles had impact on surface rheology in a mixed system with nonionic surfactant, suggesting their possible interactions with the lung surfactant system after inhalation. This preliminary investigation sets the methodological approach for further research related to the influence of inhaled PAD nanoparticles on the lung surfactant and mass transfer processes in the respiratory system.

16

Experimental and numerical study on seismic behavior of LYS and HYS steel plate shear walls connected to frame beams only

Shekastehband B., Azaraxsh A., Showkati H.

Archives of Civil and Mechanical Engineering

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2017

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Vol. 17, no. 1

154--168

EN

This paper presents an experimental and numerical investigation on the steel plate shear walls with beam-only-connected web plates (SSW-BO). These systems feature an alternative to the traditional type of steel shear walls through separating the lateral load resisting system from the primary columns. A possible drawback of SSW-BO is its reduced shear capacity compared with fully-connected web plates. High yield strength (HYS) web plate may develop shear capacity of these systems. The seismic behavior of the SSW-BO systems are experimentally investigated under cyclic quasi-static loading and compared considering two material properties and two different circular opening ratios. Shear strength, ductility, and energy dissipation capacity of HYS panels are higher than those of low yield strength (LYS) panels by as much as roughly 70%, 10% and 30%, respectively. The use of HYS web plates in SSW-BO systems appeared to be a promising solution to compensate the concerns regarding the low shear capacity and low energy dissipation resulting from separation steel plate from the columns. Moreover, the finite element software ABAQUS was used to investigate the behavior of SSW-BO systems by nonlinear analysis. A comparison between the experimental and numerical results showed excellent agreement.

17

Experimental study and modelling the evolution of viscoelastic hysteresis loop at different frequencies in myocardial tissue

Smoluk A., Smoluk L., Lisin R., Protsenko Y.

Acta of Bioengineering and Biomechanics

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2017

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Vol. 19, no. 3

11--17

EN

Our work involved experimental study of the influence of actomyosin complexes and the main structural components of the myocardial tissue – connective tissue collagen framework and cardiomyocytes – on the characteristics of viscoelastic hysteresis at different frequencies. In this paper a new method was introduced for the analysis of the viscoelastic characteristics of the force hysteresis in the isolated myocardial preparation for the assessment of mechanical energy expenditure in the tension-compression cycle. We established that basic myocardial structures have an impact on the to the characteristics of the viscoelastic hysteresis in many ways. It was shown that in rat’s myocardium cardiomyocytes one main factor that define the stiffness and viscosity of the myocardium in the physiological range of deformations, while binding of calcium ions with EGTA and calcium removal of sarcoplasmic reticulum with caffeine reduces viscoelasticity by ~30% and collagen framework is responsible for about 10% of viscoelasticity. It was revealed that in the physiological range of the hysteresis frequencies (3 to 7 Hz) expenditure of mechanical energy per unit of time increases linearly with increasing frequency. We proposed the structural and functional model that adequately describes the characteristics of the viscoelastic hysteresis in myocardial preparation in the range of strains and frequencies being under study.

18

The effect of various rapeseed oil-based polyols on selected properties of flexible polyurethane foams

Malewska E., Bąk S., Kurańska M., Prociak A.

Polimery

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2016

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T. 61, nr 11-12

799--806

EN

Bio-polyols based on rapeseed oil were used to produce flexible polyurethane foams (FPURF). The bio-polyols were obtained on a laboratory and industrial scale with the two-step method involving epoxidation of double bonds in rapeseed oil and opening of oxirane rings with different alcohols, such as isopropanol (iP) and diethylene glycol (DEG). The impact of bio-polyols production scale on selected physical and mechanical properties of FPURF was analyzed. The applied bio-polyols differed slightly by hydroxyl number, functionality, and water content. It was found that the scale of bio-polyol production has no significant impact on FPURF properties such as apparent density, hardness, hysteresis, support factor, and resilience. However, it was observed, that the addition of the bio-polyol to polyurethane (PUR) formulation had the impact on the FPURF properties as compared to the reference foams that were not modified with the bio-polyols. Moreover, a continuous method was used to prepare FPURF samples modified with different rapeseed oil-based polyols. For this purpose mixing-dosing device with conveyor line was used to synthesize the foams. It was found that the replacement of petrochemical polyols with the bio-polyols resulted in lower reactivity of the modified for- mulations and the amount of catalysts had to be increased. Furthermore, the foams hysteresis, support factor, and hardness were higher, especially for foams modified with the bio-polyol that contained DEG in its structure. Moreover, the fatigue tests were performed and the results showed a beneficial effect of the bio-based polyols on the functional properties, a.o. support factor of flexible foams.

PL

Bio-poliole z oleju rzepakowego, wytworzone w skali laboratoryjnej i przemysłowej, zastosowano wsyntezie elastycznych pianek poliuretanowych (FPURF). Bio-poliole otrzymano metodą dwuetapową przez epoksydację wiązań podwójnych w oleju rzepakowym, a następnie przez otwarcie pierścieni oksiranowych za pomocą izopropanolu (iP) oraz glikolu dietylenowego (DEG). Zbadano wpływ rodzaju bio-poliolu (także tego samego rodzaju, ale otrzymanego w różnej skali) na wybrane właściwości fizyczne i mechaniczne FPURF. Zastosowane bio-poliole różniły się między sobą nieznacznie liczbą hydroksylową, funkcyjnością i zawartością wody. Stwierdzono, że skala produkcji polioli nie ma istotnego wpływu na właściwości FPURF, takie jak: gęstość pozorna, twardość, histereza, współczynnik komfortu i odbojność. Zaobserwowano jednak wpływ modyfikacji za pomocą różnych bio-polioli na właściwości FPURF w porównaniu z właściwościami niemodyfikowanej pianki referencyjnej. Pianki FPURF otrzymano również stosując metodę ciągłą z użyciem urządzenia dozująco-mieszającego wraz zlinią do przesuwu form z mieszaniną reakcyjną. Stwierdzono, że zastąpienie polioli petrochemicznych bio-poliolami powoduje zmniejszenie reaktywności kompozycji poliuretanowych, co spowodowało konieczność zwiększenia ilości katalizatorów. Ponadto, zaobserwowano wzrost histerezy, współczynnika komfortu i twardości, szczególnie w wypadku pianek zawierających bio-poliol z wbudowanym DEG. Wyniki badań zmęczeniowych wykazały korzystny wpływ bio-polioli na właściwości użytkowe, m.in. na współczynnik komfortu pianek elastycznych.

19

Simulation tests of relay valve in the context of its resistances to motion

Tomaszewski S., Frączek J.

Pojazdy Szynowe

|

2016

|

Nr 3

39--47

EN

The article presents the description of the cylinder relay valve designed and made by the Rail Vehicles Institute "TABOR". The individual components of its construction were characterized and it was selected those that have the significant influence on change of resistances to motion of the relay valve. The currently applicable criteria concerning the operating parameters of the cylinder relay valve are presented. The selected results of the tests which consisted in determining the impact of resistances to motion on change of the hysteresis values and the correctness of operation of the relay valve are presented. The stand, on which the simulation tests of relay valve operation were carried out, and the stand for measurements of resistances to motion are shown. The article also presents a computer simulation model in which the results were verified.

PL

W artykule przedstawiono opis przekładnika ciśnienia cylindrowego zaprojektowanego i wykonanego przez Instytut Pojazdów Szynowych „TABOR”. Scharakteryzowano poszczególne elementy składowe jego budowy oraz wytypowano te, które mają istotny wpływ na zmianę oporów ruchu przekładnika ciśnienia. Przedstawiono aktualnie obowiązujące kryteria dotyczące parametrów działania przekładnika ciśnienia cylindrowego. Zaprezentowano wybrane wyniki badań, które polegały na ustaleniu wpływu oporów ruchu na zmianę wartości histerezy oraz poprawności działania przekładnika ciśnienia. Pokazano stanowisko, na którym przeprowadzono badania symulacyjne działania przekładnika ciśnienia oraz stanowisko do pomiarów oporów ruchu. W artykule przedstawiono także komputerowy model symulacyjny, w którym weryfikowano wyniki badań.

20

Influence of a skin tissue anisotropy on mechanical hysteresis

Wiśniewska A., Liber-Kneć A.

Czasopismo Techniczne. Mechanika

|

2016

|

Y. 113, iss. 5-M

125--136

EN

The mechanical properties of a pig’s skin as a human skin substitute in the studies carried out in vitro are used in surgery and engineering design. The investigation included the uniaxial tensile test and cyclic loading-unloading tests of a swine skin. The values of dissipated energy and energy dissipation ratio for first, fifth and tenth hysteresis loop of every examined sample were obtained. In the investigation, the skin anisotropy was taken into consideration. The estimation of the influence of various levels of load on the values of the measured parameters was also made.

PL

Właściwości mechaniczne tkanki skórnej świni jako substytutu skóry ludzkiej w badaniach in vitro są wykorzystywane w chirurgii i projektowaniu inżynierskim. Badania obejmowały przeprowadzenie próby jednoosiowego rozciągania oraz wykonanie testów cyklicznego obciążania-odciążenia dla skóry świni. Otrzymano wartości energii dyssypacji oraz współczynnika pochłaniania energii dla pierwszej, piątej i dziesiątej pętli histerezy mechanicznej każdej zbadanej próbki. We wszystkich przeprowadzonych badaniach uwzględniono anizotropową budowę tkanki skórnej. Oceniono także wpływ różnych poziomów zastosowanego obciążenia na wartości mierzonych parametrów.