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1
Content available Determination of hazardous metal ions in the water with resonant MEMS biosensor frequency shift – concept and preliminary theoretical analysis
Rahimi Z., Yazdani J., Hatami H., Sumelka W., Baleanu D., Najafi S.
Bulletin of the Polish Academy of Sciences. Technical Sciences
|
2020
|
Vol. 68, nr 3
529--537
EN
Heavy metal ions (e.g. cadmium, chromium, copper, nickel, arsenic, lead, zinc) have significantly serious side effects on the human health. They can bind with proteins and enzymes, altering their activity, increasing neurotoxicity, generating reactive oxygen species (ROS), promote cellular stress and resulting in their damage. Furthermore, the size, shape and type of metal are important for considering nano- or microtoxicity. It then becomes clear that the levels of these metals in drinking water are an important issue. Herein, a new micro-mechanical sensor is proposed to detect and measure these hazardous metals. The sensor consists of a micro-beam inside a micro-container. The surface of the beam is coated with a specific protein that may bind heavy metals. The mass adsorbed is measured using the resonant frequency shift of the micro-beam. This frequency shift due to the admissible mass (which is considered acceptable for drinking water based on the World Health Organization (WHO) standard) of manganese (Mn), lead (Pb), copper (Cu) and cadmium (Cd) is investigated for the first, second and third mode, respectively. Additionally, the effects of micro-beam off-center positions inside the micro-container and the mass location and investigated.
2
Content available Numerical analysis of road acoustic screen
Stempin P., Sumelka W.
Archives of Civil Engineering
|
2020
|
Vol. 66, nr 2
191--210
EN
This article presents the results of a numerical analysis of the road acoustic screen deterioration. Due to the fact that road noise barriers are located in an environment of very high corrosivity, the problem is the rusting of the metal cladding of component panels. The presented case study was, therefore, verified to fulfill the requirements presented in the Eurocode EN 1794-1. Static analysis for wind load and dynamic analysis for the load induced from vehicles was carried out. The analysis presented in the article proved the design errors and their contribution to the formation of severe corrosion, as well as demonstrating the importance of dynamic analysis in the design of acoustic screens.
PL
Drogowe ekrany akustyczne stosuje się jako ochronę przed hałasem powodowanym przez ruch samochodowy. Ze względu na bezpośrednie sąsiedztwo pasa drogowego, znajdują się one w środowisku o bardzo wysokiej korozyjności. Problemem jest więc korozja metalowych okładzin paneli akustycznych, w związku z tym podczas projektowania konstrukcji tego typu należy mieć na uwadze ograniczenie możliwości powstania korozji. W artykule zweryfikowano ekrany akustyczne zlokalizowane wzdłuż drogi ekspresowej, w których zaobserwowano silną korozję. Analizie podlegały ekrany akustyczne składające z paneli akustycznych w obudowie z aluminium. W pracy przedstawiono konstrukcję analizowanego ekranu oraz opracowano model numeryczny uwzględniający zaawansowany model panelu, w szczególności profilowany kształt, perforację blachy oraz rodzaj połączenia między okładziną i rdzeniem. Następnie przeprowadzono analizę statyczną dla obciążenia wiatrem oraz analizę dynamiczną dla obciążenia wywołanego przez pojazdy oraz sprawdzono spełnienie wymagań przedstawionych w normie EN 1794‑1 dla poszczególnych elementów składowych ekranu akustycznego. Uzyskane wyniki analiz porównano z wartościami dopuszczalnymi, wykazując nadmierne ugięcie słupów oraz w konsekwencji powstanie pomiędzy poszczególnymi panelami akustycznymi szczeliny wystarczającej do gromadzenia się czynników korozyjnych, w szczególności takich jak sól drogowa oraz piasek. Wykazano, że miejsca największego otwarcia styku pomiędzy panelami są zgodnie z miejscami występowania największej korozji analizowanych ekranów. Dodatkowo, przeprowadzone analizy dynamiczne ujawniły wzbudzenie postaci drgań mogącej się przyczynić do powstania korozji. Podsumowując, przedstawione w pracy wyniki wskazały błędy konstrukcyjne i ich wpływ na powstanie silnej korozji oraz znaczenie analizy dynamicznej w projektowaniu ekranów akustycznych.
3
Content available Large scale architectural glass slumping process - challenges and limitations
Malewski A., Kozłowski M., Sumelka W., Połedniok M.
Archives of Civil Engineering
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2020
|
Vol. 66, nr 4
485--505
EN
The paper focuses on the development of knowledge about the hot bending of curved architectural glass produced by the slumping process and the challenges as well as the limitations thereof. Due to the complexity of the process, many factors influence the final quality of the glass and the main objective was to better understand the procedure itself in order to improve the control and quality of the slumping process. As a result of the growing interest in this type of glass for architectural applications, the glass processing market is increasingly investing in the required technology. For the moment, this growing niche does not have a large number of direct explanations of the glass behaviour in the furnace in the available literature, which in turn encourages cooperation between the scientific community and manufacturers. This paper presents the conducted experiments that have led to a better understanding of the furnace's work and the impact of specific factors on its operation. Based on the 3D numerical model, a large sample of glass was produced, which was then scanned with a 3D laser using a method developed for the experiment. The results suggested that a more accurate test with usage of a full-size furnace is required. Based on this, the experiment was carried out using a large number of glass samples of different thicknesses. The results of the experiment helped to better understand and demonstrate the need for further research of this technology in order to optimize the quality of the process.
PL
W artykule skupiono się na rozwoju wiedzy na temat wielopłaszyznowego gięcia na gorąco szkła architektonicznego produkowanego w procesie opadania oraz na wyzwaniach i ograniczeniach samego procesu. Ze względu na złożoność procesu, wiele czynników wpływa na końcową jakość szkła, a głównym celem było lepsze zrozumienie samej procedury w celu poprawy kontroli i jakości procesu produkcji tego typu szkła. W związku z rosnącym zainteresowaniem tego rodzaju szkłem do zastosowań architektonicznych, rynek przetwórstwa szkła coraz częściej inwestuje w wymagane technologie. W chwili obecnej ta rosnąca nisza nie ma w dostępnej literaturze wielu bezpośrednich wyjaśnień na temat zachowania się szkła w piecu, co z kolei zachęca do współpracy pomiędzy środowiskiem naukowym a producentami. W niniejszym artykule przedstawiono przeprowadzone doświadczenia, które doprowadziły do lepszego zrozumienia pracy pieca oraz wpływu poszczególnych czynników na jego funkcjonowanie. W oparciu o trójwymiarowy model numeryczny wyprodukowano dużą próbkę szkła, która następnie została zeskanowana laserem 3D metodą opracowaną na potrzeby eksperymentu. Wyniki sugerowały, że konieczny jest dokładniejszy test z wykorzystaniem pełnowymiarowego pieca. Na tej podstawie eksperyment został przeprowadzony z wykorzystaniem dużej liczby próbek szkła o różnej grubości. Wyniki eksperymentu pozwoliły lepiej zrozumieć i wykazać potrzebę dalszych badań tej technologii w celu optymalizacji jakości procesu.
4
Content available remote State-dependent fractional plasticity model for the true triaxial behaviour of granular soil
Sun Y., Sumelka W.
Archives of Mechanics
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2019
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Vol. 71, nr 1
23--47
EN
The fractional plasticity was proposed to model the stress-strain behaviour of granular soils, but only within the scope of classical triaxial loading condition. In this study an attempt is made to develop a 3D fractional plasticity model for granular soils subjected to true triaxial loads by using characteristic stress, where all the fractional-order and integer-order derivatives can be easily obtained. Without using a plastic potential, the non-associated plastic flow rule is achieved by performing fractional derivatives of the yielding function in the characteristic stress space. The obtained plastic flow direction is found to be influenced by the fractional order, characteristic stress parameter and intermediate stress ratio. To further validate the proposed model, a series of true triaxial test results of different granular soils are simulated, from which good agreement between the model predictions and the corresponding test results is found.
5
Content available On designing the Nowacki’s device enabling the analysis of deformation and temperature in the shear zone
Łuczak B., Sumelka W., Łodygowski T.
Vibrations in Physical Systems
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2018
|
Vol. 29
art. no. 2018034
EN
In this paper a general scheme and designing challenges encountered during design of Nowacki’s shear device are presented. The novelty of the approach shown is combining 3D modelling of the whole experimental stand in Catia software with FEM simulations in Abaqus. Linking these two applications allow updating of the model effectively based on feedback from FEM analysis.
6
Content available remote Przeciwpożarowe drzwi, bramy i otwieralne okna w świetle normy PN-EN 16034:2014-11
Małkowski Z., Sumelka W.
Materiały Budowlane
|
2018
|
nr 12
93--95
PL
W artykule omówiono wybrane zagadnienia związane z wprowadzeniem zharmonizowanej normy PN-EN 16034:2014-11 i innych norm powiązanych. Szczególną uwagę poświęcono projektowaniu bram kurtynowych przeciwpożarowych o bardzo dużych wymiarach. Kluczowym problemem badawczym jest przeniesienie wyników uzyskanych w skali laboratoryjnej na skalę przemysłową.
EN
In the paper selected issues and consequences related to the introduction of the harmonized PN-EN 16034:2014-11 standard and other related standards are discussed. Particular attention is paid to the design of fire curtain gates with very large dimensions. The key research problem is how to transfer the results obtained in the laboratory to the scale needed by the industry.
7
Content available The analysis of non-linear free vibration of FGM nano-beams based on the conformable fractional non-local model
Rahimi Z., Sumelka W., Shafiei S.
Bulletin of the Polish Academy of Sciences. Technical Sciences
|
2018
|
Vol. 66, nr 5
737--745
EN
Continuum models generalized by fractional calculus are used in different mechanical problems. In this paper, by using the conformable fractional derivative (CFD) definition, a general form of Eringen non-local theory as a fractional non-local model (FNM) is formulated. It is then used to study the non-linear free vibration of a functional graded material (FGM) nano-beam in the presence of von-Kármán non-linearity. A numerical solution is obtained via Galerkin and multiple scale methods and effects of the integer and non-integer (fractional) order of stress gradient (in the non-local stress-strain relation) on the ratio of the non-local non-linear natural frequency to classical non-linear natural frequency of simply-supported (S-S) and clamped-free (C-F) FGM nano-beams are presented.
8
Content available remote A study of critical point instability of micro and nano beams under a distributed variable-pressure force in the framework of the inhomogeneous non-linear nonlocal theory
Rahimi Z., Rezazadeh G., Sumelka W., Yang X.-J.
Archives of Mechanics
|
2017
|
Vol. 69, nr 6
413--433
EN
Fractional derivative models (FDMs) result from introduction of fractional derivatives (FDs) into the governing equations of the differential operator type of linear solid materials. FDMs are more general than those of integer derivative models (IDMs) so they are more fixable to describe physical phenomena. In this paper the inhomogeneous nonlocal theory has been introduced based on conformable fractional derivatives (CFD) to study the critical point instability of micro/nano beams under a distributed variable-pressure force. The phase of distributed variable-pressure force is used for electrostatic force, electromagnetic force and so on. This model has two free parameters: i) parameter to control the order of inhomogeneity in constitutive relations that gives a general form to the model, and ii) a nonlocal parameter to consider size dependence effects in micron and sub-micron scales. As a case study the theory has been used to model micro cantilever (C-F) and doubly-clamped (C-C) silicon beams under a distributed uniform electrostatic force in the presence of von-Karman nonlinearity and their static critical point (static pull-in instability), moreover, effects of different inhomogeneity have been shown on the pull-in instability.
9
Content available On geometrical interpretation of the fractional strain concept
Sumelka W.
Journal of Theoretical and Applied Mechanics
|
2016
|
Vol. 54 nr 2
671--674
EN
In this paper, for the first time, the geometrical interpretation of fractional strain tensor components is presented. In this sense, previous considerations by this author are shown in a new light. The fractional material and spatial line elements concept play a crucial role in the interpretation.
10
Content available Analysis of the process of wood plasticization by hot rolling
Dudziak M., Malujda I., Talaśka K., Łodygowski T., Sumelka W.
Journal of Theoretical and Applied Mechanics
|
2016
|
Vol. 54 nr 2
503--516
EN
In this research, a mathematical model is derived to enable analytical determination of effective ultimate forces in the process of plasticization of the surface layer of wood. The experimentally determined thermo-mechanical properties of the material subjected to the process of plasticization are used in defining the structure of the model. The analysis of plastic strain in the layer in consideration is based on a generalised model of an ideally rigid-plastic medium, including certain modifications. Considering the anisotropic properties of wood, the Azzi-Tsai-Hill (ATH) strength criterion is applied which takes into account variation in the response of the loaded material depending on the direction. The article presents also results of FEM analysis of the same process of hot rolling of wood.
11
Content available Fractional calculus for continuum mechanics – anisotropic non-locality
Sumelka W.
Bulletin of the Polish Academy of Sciences. Technical Sciences
|
2016
|
Vol. 64, nr 2
361--372
EN
In this paper, a generalisation of previous author’s formulation of fractional continuum mechanics for the case of anisotropic non-locality is presented. The discussion includes a review of competitive formulations available in literature. The overall concept is based on the fractional deformation gradient which is non-local due to fractional derivative definition. The main advantage of the proposed formulation is its structure, analogous to the general framework of classical continuum mechanics. In this sense, it allows to define similar physical and geometrical meaning of introduced objects. The theoretical discussion is illustrated by numerical examples assuming anisotropy limited to single direction.
12
Content available remote Non-local Kirchhoff–Love plates in terms of fractional calculus
Sumelka W.
Archives of Civil and Mechanical Engineering
|
2015
|
Vol. 15, no. 1
231--242
EN
Modern continuum mechanics needs new mathematical techniques to describe the complexity of real physical processes. Recently fractional calculus, a branch of mathematical analysis that studies differential operators of an arbitrary (real or complex) order, emerged as a powerful tool for modelling complex systems. It is due to the fact that fractional differential operators introduce non-locality to the description considered in a natural way. In this sense they generalize classical (local) formulations and make the description more realistic. This paper deals with the generalisation of the Kirchhoff–Love plates theory using fractional calculus. This new formulation in non-local, thus all common fields like e.g. internal forces or displacements at a specific point contain somehow information from its finite surroundings, which is in agreement with experimental observations.
13
Wybrane aspekty bezpieczeństwa ludzi, budynków i mienia poprzez systemy ochrony pasywnej
Łodygowski T., Sielicki P. W., Sumelka W., Peksa P., Olejnik M., Puk K.
Logistyka
|
2014
|
nr 5
926--938
PL
Aktualny stan wiedzy w zakresie ochrony i bezpieczeństwa ludzi, budynków i mienia narażonych na działania terrorystyczne, a w szczególności eksplozje materiałów wybuchowych jest obecnie pomijany w polskich przepisach dotyczących infrastruktury publicznej w tym bezpieczeństwa ludzi na ulicach aglomeracji miejskiej. Wydarzenia z ostatnich lat (zamach podczas maratonu w Bostonie USA w kwietniu 2013 roku) wskazują na powiększającą się konieczność rozpatrzenia kwestii bezpieczeństwa aglomeracji miejskich, w tym w szczególności podczas imprez masowych. Niniejsza praca obejmie swym zakresem dyskusję wybranych aspektów projektowania systemów ochrony pasywnej. Wytyczne, bazują na doświadczeniach uzyskanych w trakcie wcześniejszych badań eksperymentalnych i teoretycznych oraz najnowszych osiągnięciach będących rezultatem badań w ramach grantu UOD-DEM-1-203/001, Temat: Modularny system ekranów szybkiego montażu dla ochrony ludzi, budynków i mienia przed skutkami wybuchu. Kierownik: Prof. T.Łodygowski, Politechnika Poznańska, czas trwania : 2013-2016.
EN
Extremely high pace of development force engineers to handle complicated and unusual problems. Commonly accepted design methodologies very often must undergo severe changes and improvements exceeding widely accepted standards to deliver the reliable results. The authors of this work handle complex problem of explosive loading also known as high velocity impulse loading which occurs during an impact. The class of such problems very often refers to the unusual impulse which, in particular, can be subjected to the masonry structures. These commonly used long structures can be characterized as composite material composed of two distinct sections: bricks and mortar. Moreover, the passive safety system is adopted to increase the threshold of the masonry. Additionally, the steel wired mesh and aramid fabrics are used to retrofit the brick wall.
14
Content available A note on non-associated Drucker-Prager plastic flow in terms of fractional calculus
Sumelka W.
Journal of Theoretical and Applied Mechanics
|
2014
|
Vol. 52 nr 2
571--574
EN
In this paper, we consider a special case of the general fractional plastic flow rule, namely the one which is equivalent to the classical non-associated Drucker-Prager (D-P) plasticity model. Fractional plastic flow is obtained from the classical flow rule by generalisation of the classical gradient of a plastic potential with a fractional gradient operator. It is important that, contrary to the classical models, non-associativity of fractional flow appears without introduction of the additional potential. The classical associative D-P plasticity is obtained as a special case. The discussion on objectivity of the fractional gradient is also presented also.
15
Content available remote Piotr Perzyna : Scientific Conductor within Theory of Thermo-Viscoplasticity
Glema A., Łodygowski T., Sumelka W.
Engineering Transactions
|
2014
|
Vol. 62, iss. 3
193–-219
EN
In this paper, authors reminisce on years of scientific cooperation and achievements on the personality of Piotr Perzyna and his Theory of Thermo-Viscoplasticity, which are displayed from remembrance. All the essence of latin words Master, Doctor, Docent, Professor are in some kind the reflection of the scientific history that has happened during the last 40 years. For every author the shift of 10 to 20 years shows that Piotr Perzyna served with his personality and knowledge for two to three different generations, working with authors as 20/30/50 years younger man. Now, one year after Piotr Perzyna passed away in 2013 (50 years after publishing the basic paper on Theory of Thermo-Viscoplasticity in 1963), the role he has played for authors has become much clearer and conspicuous as well as in a wider context. Like P iotr = P eter = P etrus = Kηϕας ´ Professor Perzyna is the rock on which we build. Let it remain not only in memory.
16
Content available remote Fractional continua for linear elasticity
Sumelka W., Blaszczyk T.
Archives of Mechanics
|
2014
|
Vol. 66, nr 3
147--172
EN
Fractional continua is a generalisation of the classical continuum body. This new concept shows the application of fractional calculus in continuum mechanics. The advantage is that the obtained description is non-local. This natural non-locality is inherently a consequence of fractional derivative definition which is based on the interval, thus variates from the classical approach where the definition is given in a point. In the paper, the application of fractional continua to one-dimensional problem of linear elasticity under small deformation assumption is presented.
17
Content available remote Damage induced by viscoplastic waves interaction
Łodygowski T., Sumelka W.
Vibrations in Physical Systems
|
2012
|
Vol. 25
23--32
EN
Viscoplastic waves interaction plays a fundamental role in a strain localisation phenomenon especially during highly dynamic processes occurring for example during car or orbiting space objects crashes (strain rates locally reach the values of order 107 s-1 In zones of localised deformation an intensive evolution of damage occurs which is undoubtedly directional (anisotropic) and finally may cause failure (loss of continuity). Such processes are highly influenced by the temperature (reaching often melting points) and mostly under adiabatic conditions. Mathematical description of the mentioned phenomena formulated in terms of Perzyna's thermoviscoplasticity is considered in this paper.
18
Content available remote Selected topics of high speed machining analysis.
Łodygowski M., Rusinek A., Jankowiak T., Sumelka W.
Engineering Transactions
|
2012
|
Vol. 60, iss. 1
69-96
EN
Some aspects of numerical analysis of problems related to high strain rates with thermal effects are considered. The attention is focused on constitutive modelling that describes the accompanied phenomena like plastic strain localization and softening. The importance of proper formulation of failure criteria is stressed. Also the complexity of computations is discussed.
19
Content available Nowacki's double shear test in the framework of the anisotropic thermo-elasto-viscoplastic material model
Glema A., Łodygowski T., Sumelka W.
Journal of Theoretical and Applied Mechanics
|
2010
|
Vol. 48 nr 4
973-1001
EN
In the paper, the numerical simulation of Nowacki's double shear test in the framework of recently proposed viscoplasticity theory for anisotropic solids is presented. The numerical analysis comprises the full spatial modelling and is carried out for the DH-36 steel sheet in adiabatic conditions (the analysis of anisotropic bodies can be led only on 3D models). During analyses, strain rates of order 104-107 s-1 are observed and the process time duration up to full damage (loss of continuity in the localisation zone) is around 150-300 žs. The novelty of the research is focused on the formulation that includes the anisotropy of the intrinsic microdamage process. Thus, it makes possible to obtain qualitatively and quantitatively new results compared with the existing models, like tracing the softening directions and better (closer to experiment) prediction of damage paths.
PL
W pracy przedstawiono numeryczne symulacje testu podwojnego ścinania, zaproponowanego przez prof. Nowackiego, w ramach sformułowania teorii lepkoplastyczności dla anizotropowych ciał stałych. Analizy numeryczne obejmują modele trójwymiarowe i są wykonane dla stali DH-36 w warunkach adiabatycznych (analiza ciał anizotropowych może być przeprowadzona wyłącznie na modelach trojwymiarowych). W trakcie analiz obserwuje się prędkości deformacji rzędu 104-107 s-1, a czas trwania procesu do całkowitego zerwania próbki (utraty ciągłości w strefie lokalizacji) jest z przedziału 150-300 žs. Oryginalność badań wynika z faktu uwzględnienia w definicji konstytutywnego modelu anizotropowego wewnętrznego procesu mikrouszkodzeń. W rezultacie, uzyskane wyniki dają jakościowo i ilościowo nowy obraz procesu, w szczegolności umożliwiają śledzenie kierunkow osłabienia oraz dokładniejsze (bliższe rezultatom eksperymentalnym) odwzorowanie ścieżki zniszczenia.
20
Content available remote Towards the Modelling of Anisotropic Solids
Glema A., Łodygowski T., Sumelka W.
Computational Methods in Science and Technology
|
2010
|
Vol. 16, No. 1
73-84
EN
In the paper the material model for metals and its numerical applications are presented. The material model is stated in terms of continuum mechanics, in the framework of the thermodynamical theory of viscoplasticity. The fundamental achievement is that the constitutive relation includes a description of anisotropy of metal microstructure. Such approach gives qualitatively and quantitatively new results compared with the existing models because it is possible to trace the directions of softening and predict a damage path in process time. Numerical examples comprise full spatial modelling for HSLA-65 steel in adiabatic conditions (the analysis of anisotropic bodies can be led only on 3D models) including: tension of sheet steel and twisting of thin walled tube. During analyses strain rates of order 104-107 s–1 are observed and the process time up to full damage (loss of continuity in the localisation zone) is around 100-300 mi s.
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