Wyniki wyszukiwania - BazTech

1

Development tests and FEM simulations of maximum load characteristics of medium voltage fuse links

Leśniak Anita, Szewczyk Marcin, Daszczyński Tadeusz, Piekarski Piotr

Przegląd Elektrotechniczny

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2025

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R. 101, nr 1

37--42

EN

This paper reports on development tests of the maximum load characteristics of medium voltage (MV) fuse links. The ABB motor fuse type CMF (Circuit Motor Fuse) rated at 12kV/200A was dismounted for testing of its link temperature while heating up with a rated current of 200 A. The tests were conducted for a link dismounted from a fuse and for the link mounted in a porcelain casing. The fuse casing containing the link had two options: filled with sand or left empty. While heating up, the temperature was measured on the fuse link in all cases. The tests were aimed at analyzing the impact of the environment on heat transfer from the fuse link to the environment. The tests were motivated by the adverse correlation between the overheating of the fuse links and the process of the fuse aging, which is a primary cause of their failures. The results reported so far are limited to examining the temperature at the fuse fittings and in the center of the porcelain casing. The research reported in this paper contributes to a better understanding of the behavior of the fuse links depending on the surrounding environment to which the heat is dissipated from the fuse links. A Finite Element Method (FEM) model was developed and qualitatively validated against the testing results. The model is suitable for allowing qualitative assessment of the fuse heating in an environment with limited heat exchange.

PL

W artykule przedstawiono badania rozwojowe charakterystyk maksymalnego obciążenia wkładek bezpiecznikowych średniego napięcia (SN). Bezpiecznik silnikowy ABB typu CMF (Circuit Motor Fuse) o napięciu 12kV/200A został zdemontowany w celu sprawdzenia temperatury jego topika podczas nagrzewania prądem znamionowym 200 A. Badania przeprowadzono dla topika zdemontowanego z bezpiecznika oraz dla osadzonego w porcelanowej obudowie. Badania wykonano dla dwóch układów: bezpiecznik wypełniony piaskiem lub pusty. Podczas nagrzewania we wszystkich przypadkach mierzono temperaturę na wkładce bezpiecznikowej jak i topiku. Badania miały na celu analizę wpływu otoczenia na przenikanie ciepła z wkładki topikowej do otoczenia. Motywacją do przeprowadzenia badań była negatywna korelacja pomiędzy przegrzaniem wkładek bezpiecznikowych a procesem starzenia się bezpieczników, który jest pierwotną przyczyną ich awarii. Dotychczasowe wyniki ograniczają się do badania temperatury na obudowach bezpieczników i w środku porcelanowej obudowy. Badania przedstawione w tym artykule przyczyniają się do lepszego zrozumienia zachowania wkładek topikowych w zależności od otaczającego środowiska, do którego odprowadzane jest ciepło z wkładek topikowych. Opracowano model metody elementów skończonych (MES), który poddano walidacji jakościowej w oparciu o wyniki testów. Model umożliwia jakościową ocenę nagrzewania się bezpiecznika w środowisku o ograniczonej wymianie ciepła.

2

Static modelling wooden modular construction

Dzun Michał, Miedziałowski Czesław

Materiały Budowlane

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2025

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nr 3

1--9

EN

The article systematically presents the modelling of individual stages of creating wooden modular buildings with static diagrams. Descriptions of modelling the connections of the frame and sheathing boards in elements (ceiling walls) are provided. Presented models of connections using pins and connectors in the form of nails and screws. The creation of modular structures in frame and plate systems is presented. Then, the vertical and horizontal connection between the modules in the building structure was presented. Finally, the creation of a global computational model of the structure was shown, taking into account the modelling of components (walls, floors), modules and entire buildings.

PL

W artykule przedstawiono w sposób systematyczny modelowanie schematami statycznymi poszczególnych etapów tworzenia drewnianych budynków modułowych. Podano opisy modelowania połączeń szkieletu i płyt poszycia w elementach (ściany, stropy). Zaprezentowano modele połączeń na trzpienie oraz za pomocą łączników w postaci gwoździ i wkrętów, a także tworzenie struktur modułowych w układzie szkieletowym i płytowym. Następnie przedstawiono połączenie w pionie i w poziomie między modułami w konstrukcji budynków oraz pokazano tworzenie globalnego modelu obliczeniowego konstrukcji, uwzględniając modelowanie elementów składowych (ścian, podłóg), modułów i całych budynków.

3

Numerical simulation of nuclear blast wave impact on protective elements of anthropogenic structures

Kosiuczenko Krzysztof

Inżynieria Bezpieczeństwa Obiektów Antropogenicznych

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2025

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Nr 1

12--22

EN

The paper presents the use of LS-DYNA software for numerical simulation of nuclear blast wave effects on protective structures. Brode's function was employed for blast wave modeling, and the Johnson-Cook material model was used to describe steel behavior. The results indicate the effectiveness of combining empirical methods with advanced numerical models in analyzing these types of phenomena.

4

Analytical and numerical investigation of free vibration of nanoparticle-reinforced composite cylindrical shells

Abbas Ehab N., Abud Ali Zaman Abud Almalik, Njim Emad Kadum, Flayyih Mujtaba A., Madan Royal

Diagnostyka

|

2025

|

Vol. 26, No. 1

art. no. 2025112

EN

This study focuses on the characterization of free vibration of composite shell structures strengthened by different volume fractions of nanoparticles analytically and numerically. Using simply supported boundary conditions, the governing differential equation of motion for the shell was formulated based on the DonnellMushtari-Vlasov (DMV) shell theory. For different design parameters, the natural frequency was investigated by employing the Orthogonality method. Four different layers of material, namely Perlon, Carbon, Kevlar, and Kenaf, of thickness 30 mm, were made. Nanoparticles Alumina (Al2O3) and Silica (SiO2) were chosen and mixed in varying volume fractions (0.5%, 1%, 1.5%, 2%, and 2.5%) for the sample fabrication. Two types of samples, A and B, were created based on the arrangement of layers. The tensile tests were performed on the fabricated specimens to identify the longitudinal Young’s modulus of specimens. The two groups that consist of different layers of materials were made and named as group A and group B. The results indicate an increase in Young’s modulus of 33.9% increase for nano Al2O3 and a 42.25% increase for nano SiO2 at a volume fraction of 2.5% for group A, while for group B, the enhancement was 37.96% and 47.39% for Al2O3 and SiO2 nanoparticles, respectively. The results indicate that as the volume fraction of nanomaterial is increased, the natural frequency increases. The experimental results are used to validate both analytical and numerical solution conducted by the finite element method (FEM) under various loading conditions. The maximum difference between the analytical and numerical prediction of the natural frequency results was within 5%.

5

Numerical analysis of the strength and stiffness of triggo light electric vehicle body

Stachowicz Łukasz, Boczkowska Anna, Budweil Rafał

Composites Theory and Practice

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2025

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R. 25, nr 1

38--48

EN

TRIGGO is one of the first vehicles to effectively combine the manoeuvrability and parking advantages of twowheelers with the safety and comfort features comparable to those of small passenger cars. It is intended for use in a short-term rental network and should be characterised by low energy consumption. To this end, it is reasonable to optimise the vehicle's design towards minimising weight. The use of composites in the TRIGGO body structure enabled a reduction in the ready-to-drive vehicle weight and optimal utilisation of the available space. This choice makes it possible to keep the body weight low while ensuring appropriate mechanical properties. The subject of this paper is numerical analyses of the strength and stiffness of the TRIGGO light vehicle body made of glass-epoxy composites. The scope of the work includes the construction of a computational model of the TRIGGO vehicle body made by the RTM method with a double skin and foam core, in addition to calculations of the stiffness and strength of the structure during body load tests. For this purpose, an FEM computational model was built based on the 3D body model. The body of the RTM version of the TRIGGO vehicle consists of 27 separate components, which are connected to each other by rigid bonded contacts. The composite structures with foam cores were modelled as single-layer shell elements including all the layers of the composite, and a foam spacer. Three design cases were developed: P1.1 - vertical-transverse body loading, P1.2 - vertical-longitudinal body loading, P1.3 - vertical-longitudinal body loading with a horizontal force component. The calculation cases were determined based on "Regulation (EU) No 168/2013 of the European Parliament and of the Council with regard to requirements for the functional safety of vehicles for the approval of two- or three-wheel vehicles and quadricycles", in particular Annex XI of this document. The calculations prove that the glass-epoxy body of the TRIGGO light vehicle meets the requirements for strength and stiffness.

6

New technique for sharpening ultra-thin wires for the drawing process: incremental furnace stretching

Kustra Piotr, Milenin Andrij

Bulletin of the Polish Academy of Sciences. Technical Sciences

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2025

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Vol. 73, nr 2

art. no. e153425

EN

In the wire drawing process, the wire is subjected to sharpening before each drawing. Traditional methods for sharpening wires involve one of the following techniques: crimping, grinding, rolling, chemical etching, or stretching within a furnace. Wire sharpening becomes especially difficult in the manufacture of ultra-thin wire. This study proposes and examines a novel technique for sharpening thin and ultra-thin wires through specialized stretching in a furnace. This study proposes and investigates a new technique for sharpening thin and ultra-thin wires based on stretching them in the furnace. Using a rheology-based concept of wire deformation during stretching, this study offers a substantial enhancement in the maximum attainable thinning of the wire during sharpening. Technically, this advancement is achieved by transitioning from a single-stage stretching process to an incremental one, characterized by small increments of deformation at each stage. In addition to incremental stretching, the proposed method includes simultaneous movement of the wire through a continuous micro furnace, repeated at each stage of elongation, which achieves thinning of the wire end of a given length. This study theoretically and experimentally explores further potentialities of this approach concerning the fabrication of ultra-thin wire. The findings show that the effectiveness of the proposed method strongly depends on the shape of the stress-strain curve of the wire material. For example, the conducted research demonstrated that this method is more effective for brass than for copper wire.

7

Equilibrated residual method for estimation of modelling and approximation errors in complex piezoelectric models

Zielińska Magdalena, Zboiński Grzegorz

Bulletin of the Polish Academy of Sciences. Technical Sciences

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2025

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Vol. 73, nr 2

art. no. e153228

EN

The article presents the equilibrated residual method (ERM) of error estimation in coupled problems in the case of complex piezoelectric models. These models include hierarchical, first-order, and transition models within the mechanical field of displacements, as well as hierarchical models within the electric field of potential. Three (classical, modified and enhanced) transition models are considered. The paper presents a variational formulation of the model problem of general piezoelectricity in the case of complex piezoelectric models and the finite element approximation of this problem. Next, the equilibration residual method for coupled problems of piezoelectricity and complex piezoelectric models is presented. The mechanical, electric and coupled parts of the modelling, approximation and total error estimators, and true errors are given. Effectivity indices (the ratio of estimated error to true error) are used to assess the quality of error estimation in the case of three error parts and three types of error for the complex models of piezoelectric plates. The effectivity results for simple piezoelectric models and uncoupled problems of elasticity and dielectricity are applied as references.

8

Determination of wind force acting on an object in the shape of a bent pipe

Padewska-Jurczak Agnieszka, Buliński Zbigniew, Krysiński Tomasz

Bulletin of the Polish Academy of Sciences. Technical Sciences

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2025

|

Vol. 73, nr 1

art. no. e152706

EN

The aim of the paper is to determine the aerodynamic forces acting on a torus-shaped structure fragment at high wind velocity which are impossible to obtain from the existing standard EN 1991-1-4 (the so-called wind standard). The most important problem is the correct modeling of turbulence and laminar-turbulent transition in the conditions of flow interference resulting from the presence of other obstacles. For this reason, forces are obtained by two methods: fluid-structure interaction (FSI, force transfer) and user-defined functions (UDF). Variations of the total aerodynamic lift force of the half of the torus with angle β and velocity of wind w, and the formula for estimating the horizontal force Pz perpendicular to drag force are presented. Additionally, useful engineering parameters (such as pressure distribution and air velocity field) are determined. The forces of wind influence on two cylinders and a torus-shaped object are obtained and compared.

9

The natural oscillations of perforated sifting surfaces with epicycloidal holes

Kharchenko Serhii, Samborski Sylwester, Paśnik Jakub, Kharchenko Farida

Advances in Science and Technology. Research Journal

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2025

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Vol. 19, no. 1

256--268

EN

The use of vibrational perforated sifting surfaces with holes of complex geometry provides intensive separation of loose materials by particle size and increases the technological efficiency of separating equipment. The lack of research methodologies and data on the oscillations of such perforated surfaces limits their application in practice, requires reliability studies and the derivation of appropriate patterns. The reliability analysis was conducted by studying the natural oscillation frequencies of perforated surfaces and checking for the absence of resonance phenomena. For the research, the methodology is based on numerical finite element methods in Abaqus_CAD and allows analyzing the natural oscillations of the structure when its structural parameters and boundary conditions are varied. To study the level of influence of the design of epicycloidal holes on the natural oscillations of perforated sifting surface, the identification of their values for round, epicycloidal (with a modulus of 5, 7 and 9) hole shapes was carried out. Patterns of variation in the natural oscillation frequencies of perforated surfaces are obtained depending on significant factors: surface thickness, hole spacing and epicycloid modulus. In addition, the analysis involved studying eight common modes of oscillation encountered in practice. The results were a research methodology, mathematical expressions for simplified calculation and analysis, patterns of oscillation changes of perforated sifting surfaces with holes of complex geometry. Studies enable the prediction of resonance phenomena and damage between the holes of perforated sifting surfaces, the absence of which determines their reliability.

10

Innovative method of rolling railcar axles using segmented tool assemblies

Pater Zbigniew, Tomczak Janusz, Shu Xuedao, Li Zixuan

Advances in Science and Technology. Research Journal

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2025

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Vol. 19, no. 3

271--282

EN

This paper presents a novel method for rolling railcar axles using wedge tools of considerable length (about 8 m). The tools are divided into 28 components which are mounted in a tool assembly that moves in a way resembling caterpillar drive. The advantages of the proposed method include no tool idling and relatively low forming loads. A design of a segmented rolling mill with two identical tool assemblies is presented. The feasibility of the proposed solution is verified via numerical simulations conducted in Simufact.Forming. A rolling process for producing a BA3002 type railcar axle from both a cylindrical and a rectangular billet is analysed in detail. Maps of effective strain, temperature and damage function in the workpiece are shown for both cases considered. These maps clearly show that a rail axle of good quality is obtained in both rolling processes. In addition, by analysing the forming load distributions, the power of the rolling mill drive system was also estimated, which was found to be significantly higher in the case of rolling from a rectangular billet.

11

Application of the numerical simulation method for the strength analysis of long-term portal crane components

Lipiec Sebastian, Zvirko Olha, Dzioba Ihor, Venhryniuk Oleh

Advances in Science and Technology. Research Journal

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2025

|

Vol. 19, no. 4

126--139

EN

In this paper, the strength analysis of the material from two elements of a portal crane operated for about 33 years was carried out. The assessment was based on modelling and numerical simulation results using the finite element method of the load of three-point bending specimens. The constitutive relationships of the materials in the form of true stress-strain relationships were defined based on data from the uniaxial tensile test of the appropriate specimens. The iterative fitting method of the experimental and numerical relationship and the method that considers triaxiality and the Lode parameter were used. The accuracy of the defined stress-strain relationships was verified by comparing the load curves determined experimentally and numerically. Numerical modelling and simulation of the load of three-point bending specimens allowed obtaining stress distributions before the crack tip and the values of fracture toughness – J-integral. The results of the numerically calculated J-integral are similar to the experimental results. The trends in the stress component distributions indicate a high level of fracture toughness of the tested materials, ensuring a ductile nature of subcritical crack growth. The proposed methodology can be applied to other steels of operated structures.

12

Analysis of wing in ground-craft water landing

Rośkowicz Marek, Chachurski Ryszard, Omen Łukasz, Jędrak Michał

Advances in Science and Technology. Research Journal

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2025

|

Vol. 19, no. 3

144--157

EN

Unmanned aerial platforms, along with surface platforms, can be elements of rapid response force systems at sea. The USV-UAV-WIG (Unmanned Surface Vehicle, Unmanned Arial Vehicle, Wing in Ground Effect) platform is a type of vehicle that combines the features of an aircraft and a surface vehicle. In its operational range, it moves using the so-called ground effect. This phenomenon consists in increasing the lift of an aircraft moving at a small height above the ground or water (the height is assumed to be half the wing span). To consider this problem, we first prepared a computational task for the impact of a ball, box, and cylinder-shaped bodies on water. The calculations were carried out using the finite element method using the capabilities of the LS-DYNA environment. Computer simulations of impact of the those shaped bodies on water were experimentally verified using the so-called high-speed camera and the image analysis system. Second, analytical calculations and numerical simulations of the launch of an example USV-UAV-WIG structure were carried out. For the purposes of the analyses, a numerical model of the structure and a model of the water-solid interaction were prepared. On the basis of the results of the calculations obtained, the loads occurring during landing of the vehicle were defined.

13

Assessment of the influence of the bending form shape on the stress and plastic strain values in a cold bending pipe

Nozdrzykowski Krzysztof, Stępień Mateusz, Grządziel Zenon

Zeszyty Naukowe Politechniki Morskiej w Szczecinie

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2024

|

nr 78 (150)

35--48

EN

Abstract This paper presents the results of modelling research concerned with the technological process of the cold bending of a pipe. Stress and plastic strain studies are carried out using the finite element method (FEM) on a thick-walled pipe and various shapes of bending form. The results of the research are benchmarked in terms of the correctness of the implementation of the bending process, including the change in the pipe outside diameter and wall thickness. The level of ovalisation of the cross-section in the bending pipe is used as the primary criterion for assessing the correctness of the bending process. The results show that the most favourable properties in terms of minimising the ovalisation of the pipe cross-section are provided by the use of a bending form with a trapezoidal shape.

14

Formulation of the critical lateral buckling moment of a steel I-beam

Derlatka Anna, Gao Shan

Zeszyty Naukowe Politechniki Częstochowskiej. Budownictwo

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2024

|

Z. 30 (180)

23--28

EN

The paper presents an analysis of the method of formulation of the critical lateral moment during buckling of an I-beam. Three methods of determining the critical moment were considered: commonly known analytical formulas, the Robot Structural Analysis Professional 2024 program and the finite element method implemented in the ADINA program. The subject of the analysis was the steel beam with a cross-section of IPE 200. Two simply supported beams were considered. The first one was loaded with a concentrated force and the second one was loaded with an evenly distributed load.

PL

Przedstawiono analizę sposobu obliczania momentu krytycznego przy zwichrzeniu belki dwuteowej. Rozważano trzy sposoby wyznaczania momentu krytycznego: powszechnie znane wzory analityczne, program Robot Structural Analysis Professional 2024 oraz metodę elementów skończonych zaimplementowaną w programie ADINA. Przedmiotem analizy była belka stalowa o przekroju IPE 200. Rozważano dwie belki swobodnie podparte. Pierwszą obciążono siłą skupioną, a drugą obciążono obciążeniem równomiernie rozłożonym.

15

Assessment of reinforced concrete beams cracking depending on the concrete class

Derlatka Anna, Jrethi Yassin Ali

Zeszyty Naukowe Politechniki Częstochowskiej. Budownictwo

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2024

|

Z. 30 (180)

29--34

EN

Cracks in reinforced concrete are a common concern that can arise from various causes such as concrete shrinkage, temperature differences, and structural loads. The aim of the study was an analysis of cracks in concrete on which the reinforcement concrete beam was made. The beam was loaded with an evenly distributed load and subjected to bending. Depending on the concrete class (C20/25, C25/30 and C30/37), the cracks in the concrete, the deflection at a load of 5.35 kN/m2 and the beam’s load-bearing capacity, i.e. the value of the load that the beam can withstand without any cracks were assessed.

PL

Pęknięcia w żelbecie są powszechnym problemem, który może wynikać z różnych przyczyn, takich jak skurcz betonu, różnice temperatur i obciążenia konstrukcyjne. Celem pracy była analiza pęknięć w betonie, z którego wykonano belkę żelbetową. Belka została obciążona równomiernie rozłożonym obciążeniem i poddana zginaniu. Analizowano trzy klasy betonu C20/25, C25/30 i C30/37. W zależności od klasy betonu oceniano pęknięcia w betonie, ugięcie przy obciążeniu 5.35 kN/m2 i nośność belki, tj. wartość obciążenia, jakie belka może wytrzymać bez pęknięć.

16

Piezoelectric disc based sensor-actuator hybrid in vibration reduction

Trojanowski Roman

Vibrations in Physical Systems

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2024

|

Vol. 35, nr 1

art. no. 2024117

EN

This paper presents the results of comparison of vibration reduction levels between standard disc based piezo actuators and piezoelectric sensor-actuator hybrids. Modelling was done using FEM method in ANSYS software. Model consisted of a steel plate with piezo elements attached. A square based element was used as an actuator to excite plate’s vibrations. Disc based element which was either a standard homogeneous disc based actuator or a sensor actuator hybrid with 2 possible sizes of the sensor part of said hybrid. Harmonic analyses were performed for the 1st, 2nd, 4th and 5th mode shapes with the goal function being the minimalization of displacement vector sum of a number of nodes (there were 3 possible cases). Significant vibration reduction levels were obtained with no significant differences in said levels between standard actuators and sensor-actuator hybrids. Reducing the size of sensor part of sensor-actuator allowed for lower voltages needed to achieve vibration reduction levels.

17

Innovative FEM for the thermal analysis of architectural glazing exposed to solar radiation. Proposal for a simplified engineering approach

Galuppi Laura, Maffeis Massimo, Haydar Ali, Royer-Carfagni Gianni

Świat Szkła

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2024

|

R. 29, nr 9

2--5

18

Cold forming of steel - selected processes, issues, and CAx

Horajski Piotr

Systemy Wspomagania w Inżynierii Produkcji

|

2024

|

Vol. 13, iss. 1

41--54

EN

This paper presents an analysis of the key challenges and irregularities associated with metal plastic deformation processes, with particular emphasis on phenomena such as springback, wrinkling, folding, cracking, microcracking, and burr formation. These undesirable effects can negatively impact the quality of final products and their mechanical properties, as well as the durability of tools used in processes such as bending, stamping, spinning, and cutting. The paper discusses the mechanisms leading to the formation of these defects, highlighting the role of process conditions, such as stress, processing speed, and tool geometry, which can cause technological issues. It also emphasizes the significance of tool wear, particularly in cutting processes, where abrasive, adhesive, and fatigue wear can lead to burr formation and deterioration in the quality of cut components. The study further explores methods to minimize these defects through process parameter optimization and proper tool design. Special attention is given to the use of numerical tools, such as the finite element method (FEM), which enables precise modeling of stress and strain distributions and the prediction of potential defect locations. Advanced simulations allow for improved prediction of issues like cracking, wrinkling, and springback, which ultimately enhances the quality of deformation processes and final products. The paper also highlights the need for further research in plastic deformation and the development of numerical models, particularly in the context of accounting for microstructural changes and residual stresses in materials.

PL

Niniejsza praca przedstawia analizę kluczowych wyzwań i nieprawidłowości związanych z procesami deformacji plastycznej metali, ze szczególnym uwzględnieniem takich zjawisk jak powrót sprężysty, marszczenie, fałdowanie, pękanie, mikropęknięcia oraz powstawanie gratu. Te niepożądane efekty mogą negatywnie wpływać na jakość finalnych produktów oraz ich właściwości mechaniczne, a także na trwałość narzędzi wykorzystywanych w procesach, takich jak gięcie, tłoczenie, wyoblanie czy cięcie. W pracy omówiono mechanizmy prowadzące do powstawania tych wad, zwracając uwagę na rolę warunków realizacji procesu i zjawisk fizycznych, takich jak naprężenia, prędkość obróbki oraz geometrię narzędzi, które mogą prowadzić do problemów technologicznych. Podkreślono również znaczenie zużycia narzędzi, w szczególności w kontekście procesów cięcia, gdzie zużycie cierne, adhezyjne oraz zmęczeniowe może prowadzić do powstawania gratu oraz pogorszenia jakości ciętych elementów. Analizowano także metody minimalizowania wspomnianych wad poprzez optymalizację parametrów procesowych i odpowiednie projektowanie narzędzi. Szczególną uwagę poświęcono wykorzystaniu narzędzi numerycznych, takich jak metoda elementów skończonych (MES), która pozwala na precyzyjne modelowanie rozkładów naprężeń, odkształceń oraz przewidywanie miejsc potencjalnych wad. Dzięki zaawansowanym symulacjom możliwe jest lepsze przewidywanie zjawisk takich jak pękanie, fałdowanie czy powrót sprężysty, co pozwala na poprawę jakości procesów deformacyjnych i produktów końcowych. Wskazano również na potrzebę dalszych badań w zakresie obróbki plastycznej oraz rozwoju modeli numerycznych, szczególnie w kontekście uwzględniania zmian mikrostrukturalnych i naprężeń resztkowych w materiałach.

19

Analiza układów z tłumieniem wewnętrznym

Hać Michał

Przemysł Chemiczny

|

2024

|

T. 103, nr 12

1454-1456

PL

Omówiono zagadnienie zapisu tłumienia materiałowego w układach fizycznych w przypadku sformułowania równań ruchu w postaci macierzowej (np. za pomocą metody elementów skończonych) i dla układów ruchowych (mechanizmy, układy wirujące). Sformułowano model zapisu macierzy tłumienia materiałowego w przypadku uwzględnienia wzajemnej zależności między ruchem drgającym a ruchem zadanym układu. Jako przykład ilustrujący wpływ tłumienia na drgania członów mechanizmu rozpatrzono układ korbowo-wodzikowy mający zastosowanie w maszynach w wielu gałęziach przemysłu.

EN

The problem of modelling material damping in phys. systems was discussed in the case of formulating the equations of motion in the matrix form (used e.g. in finite element method) and for motion systems (mechanisms, rotating systems). A model of material damping matrix was formulated in the case of taking into account the mutual dependence between the vibration motion and global mechanism motion. In order to assess the effect of damping on vibration of mechanical members, a slider crank mechanism was considered.

20

Performance evaluation of cap and pin insulator under pollution conditions using Finite element method (FEM)

Zorig Assam, Belhouchet Khaled, Ouchen Lyamine

Przegląd Elektrotechniczny

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2024

|

R. 100, nr 9

142--145

EN

Insulators with High voltage are the key components in energy transmission systems wich may be affected by pollution. In this paper, the performance of a cap and pin insulator is investigated with the objective of predicting the propagation of an AC surface arc on contaminated insulators in the presence of a non- uniform electric field. To assess the performance of the insulator, the electric field simulation is carried out by using the finite element method. Research results show that non-uniform contamination had the worst electric field profile. This work can provide a useful tool for the design and maintenance of cap and pin insulators.

PL

Izolatory wysokiego napięcia są kluczowymi elementami systemów przesyłu energii, na które mogą mieć wpływ zanieczyszczenia. W tym artykule zbadano działanie izolatora kołpakowo-kołkowego w celu przewidzenia propagacji łuku powierzchniowego prądu przemiennego na zanieczyszczonych izolatorach w nierównomiernym polu elektrycznym. Aby ocenić skuteczność izolatora, przeprowadza się symulację pola elektrycznego metodą elementów skończonych. Wyniki wskazują, że zanieczyszczenie niejednorodne miało najgorszy profil pola elektrycznego. Praca ta może dostarczyć przydatnego narzędzia do projektowania i konserwacji izolatorów kołpakowych i kołkowych.