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1

Experimental-Numerical Analysis of a Flat Plate Subjected to Shearing and Manufactured by Incremental Techniques

Kopecki Tomasz, Święch Łukasz

Advances in Science and Technology. Research Journal

|

2023

|

Vol. 17, no 4

179--188

EN

The paper presents the results of experimental studies and numerical analyses using the Finite Elements Method for a planar structure subjected to pure shear. The test specimen was made using an Fused Filament Fabrication incremental technique. In order to correctly represent the mechanical properties of the structure, a series of tests were performed to determine the physical constants of the model material used. Due to the perfect physical nature of the numerical model, in contrast to experimental phenomena, a suitable method was employed to induce the post-critical deformations in the analysed structure.

2

Modelling of strengthening of concrete beams with FRP in Ansys software

Kowalski Damian, Selejdak Jacek

Materiały Budowlane

|

2022

|

nr 11

188--191

EN

The purpose of this article is to confirm an accuracy of Cohesive Zone Model (CZM) implemented in Ansys for modelling concrete beams strengthened with fiber reinforced polymer (FRP) tapes. Only mode II of debonding was taken into account, which is sufficient for a case of bent beam strengthened with FRP tape glued to its bottom. Results show satisfying coincidence of used model with experimental data and therefore confirm usefulness of CZM for solving the above mentioned problems.

PL

Celem artykułu jest weryfikacja dokładności modelu Cohesive Zone Model (CZM), zaimplementowanego w programie Ansys, w modelowaniu numerycznym belek żelbetowych wzmacnianych taśmami z polimerów zbrojonych włóknami (FRP). Wzięto pod uwagę jedynie postać II utraty przyczepności, co jest wystarczające w przypadku belek zginanych wzmocnionych taśmą przyklejoną do ich spodu. Wyniki pokazują zadowalającą zgodność użytego modelu z danymi eksperymentalnymi i tym samym potwierdzają użyteczność CZM do rozwiązywania ww. zagadnień.

3

Numerical Analysis of the Impact of Geometric Parameters of the Outcuts in the Wing Torsion Box Wall on the Mechanical Properties of the Structure

Kopecki Tomasz

Advances in Science and Technology. Research Journal

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2022

|

Vol. 16, no 3

176--182

EN

The study presents the results of comprehensive numerical analyses of an unusual solution in the field of geometry of holes in the wall of the wing torsion box subjected to torsion. Due to the nature of loads acting on the wing structure in flight conditions, it is possible to modify the current standard solutions. However, this involves a fundamental change in the nature of stress distribution and the resulting need to use new types of local reinforcements of the structure. The analyses were supposed to indicate the dependencies between the geometric parameters of the outcuts and the nature of advanced deformations and the distribution of internal forces.

4

Selected Methods of Obtaining Adequate Forms of Deformation of Supercritical Thin-Walled Flat Plates

Kopecki Tomasz

Advances in Science and Technology. Research Journal

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2021

|

Vol. 15, no 2

184--190

EN

The study includes considerations on the numerical methods of obtaining the correct forms of deformation of thin-walled plates subjected to pure shear, operating under conditions of critical loads. Selected methods were presented and subjected to comparative tests, allowing for the obtaining of a state of large deformations of a perfectly flat system, loaded in its plane. These methods are based on application various forms of initial imperfections into the system, either geometrically or physically. A new solution was proposed in this area, differing in its essence from most commonly used solutions.

5

Influence of machining accuracy of links on dynamic response of planar mechanisms

Hać Michał

Vibrations in Physical Systems

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2020

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Vol. 31, nr 2

art. no. 2020207

EN

In the paper the influence of machining accuracy of mechanism links on their dynamic response is under investigation. As an example a of planar slider-crank mechanism is studied. The influence of different cross-section area within the assumed tolerance on the dynamic behaviour of mechanism’s connection rod is investigated. For vibration analysis of links the finite element method is used with Bernoulli-Euler beam elements. The calculation were conducted for nominal dimensions of the cross section of the crank and for the two cases for connecting rod: 1) for the maximal stiffness and 2) for the minimal stiffness obtained within the given tolerance. The results of analysis show that the changes in dynamic response for different cross-sectional area of mechanism links, within the assumed tolerance of machining, can be quite significant in the case of high-speed precise mechanisms and manipulators.

6

Finite element analysis of natural frequencies and mode shapes of the da Vinci medical robot arm

Geda Helena, Kuliberda Agata, Stręk Tomasz

Vibrations in Physical Systems

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2020

|

Vol. 31, nr 2

art. no. 2020205

EN

This paper presents an analysis of the natural frequency and mode shapes of the arm and the working tip of the da Vinci robot, which is used in various types of surgical procedures. The survey was conducted using Autodesk Fusion 360. Using the da Vinci robot's construction data, a model was designed taking into account the characteristic dimensions and materials used. The obtained shapes of vibrations for natural frequencies allowed us to predict the influence of resonance phenomenon on the manipulator's arm. The movement of the tool along the wrong track, caused by an increase in vibration amplitude, may adversely affect the operation of the device. The results of the conducted research, therefore, provide information for which natural frequencies the values of these amplitudes increase.

7

Analysis of eigenfrequencies of the foot prosthesis with auxetic component layer

Łączna Daria, Dłużniewski Filip, Stręk Tomasz

Vibrations in Physical Systems

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2020

|

Vol. 31, nr 2

art. no. 2020214

EN

In this paper, natural frequencies of a three-layered foot prosthesis are investigated. The model of foot prosthesis consisted of a three-layered base, which substitutes a human foot and an element in the shape of an arc that represents a shank of human. The base consists of three layers made of carbon fiber. In the lower part of the prosthesis, the auxetic layer is used as the inner layer. Numerical analysis is made for different parameters of the central layer: the thickness and the value of Poisson’s ratio. The simulations are used to investigate the influence of an auxetic layer on prosthesis vibrations and compare the impact of different parameters on results. Calculations are made using the finite element method implemented in Autodesk Fusion 360. The results show that the auxetic layer has a great impact on tolerance to vibrations and mobility.

8

An analysis of the auxetic cranioplasty implant

Maciejewska Jagoda, Jopek Hubert

Vibrations in Physical Systems

|

2020

|

Vol. 31, nr 3

art. no. 2020315

EN

The following paper is a reflection on the advisability of using auxetic structures in medical devices. For this purpose, a model of a skull implant was designed. This implant could be used for cranioplasty of bone defects after neurosurgical procedures. The implant is made of a titanium alloy and has an auxetic "double arrow" structure. The behavior of the implant was investigated in two cases, under the influence of increased intracranial pressure and impact of an external force. The calculations were made with the finite element method implemented in the SolidWorks 2020 program. Moreover, the natural frequency of the structure was examined in the Comsol Multiphysics program.

9

An analysis on the effect of crosscuts within shaft protective pillars on deformations of the surrounding rock mass deformations

Warchala Ewa, Szostak-Chrzanowski Anna

Mining Science

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2020

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Vol. 27

253--265

EN

The development of crosscuts within mining shafts’ protective pillars causes a change of state of stress in the surrounding rock mass. It also causes deformations of the rock mass and the surface. It is essential to conduct prediction analysis of the deformations and stresses in order to secure a proper functioning of a shaft located within the protective pillar. It is recommended that the analysis should be based on the integration of the finite element method (FEM) and geodetic monitoring results. FEM makes it possible to determine the rock mass stresses and displacements in the shaft protective pillars and in the surrounding rock mass. It makes is possible to determine the safety and proper functioning of the shaft. The results of the FEM analysis of the impact of crosscuts and mining activities on rock mass deformations inside and on the surface of the protective shaft pillar are presented. The influence of mining extractions was investigated. The mining panels were located around the safety pillar in three regions NW, SE and SW and the crosscut were located within the safety pillar. The presented methodology will allow for the determination of the deformations and strains in case of farther development of crosscuts within the protective shaft pilar and by planned mining activities around the pillar.

10

Analysis of the Post-Critical Deformation State of Curvilinear Integral Stiffening of a Thin-Walled Structure Subjected to Torsion

Kopecki Tomasz

Advances in Science and Technology. Research Journal

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2020

|

Vol. 14, no 2

34--40

EN

The paper presents an innovative concept of integral stiffening of the thin-walled structures based on the use of curvilinear elements. The analyzed system in the form of a thin-walled spatial structure was subjected to a non-linear numerical analysis, aimed at comparing the properties of the proposed solution with those of the reference stiffening. A comparative analysis of deformation forms and ranges as well as effective stress distributions was conducted. The tests constituted a preliminary analysis, aimed at determining the usability of the solution, which is the basis of the research process supported by an appropriate experiment.

11

Torque simulation in a reluctance motor design incorporating HTS materials in both stator and rotor parts

Bouchekhou Hocine, Mekideche Mohamed Rachid, Lévêque Jean

Przegląd Elektrotechniczny

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2019

|

R. 95, nr 9

94--97

EN

In this work, a fully high temperature superconducting reluctance motor (HTS RM) is studied. A smallest configuration of HTS armature winding based on the mechanical characteristics of HTS BSCCO tape is determined. Furthermore, a novel rotor topology of single HTS YBCO bulk with ferromagnetic material is proposed. Electromagnetic torque of HTS RM is calculated by finite element method (FEM) with 2D consideration. The characteristics of the bipolar HTS RM are compared with a conventional motor with HTS rotor.

PL

Opisano silnik reluktancyjny z elementami wykonanymi z wysokotemperaturowego nadprzewodnika. Do uzwojenia wykorzystano taśmę HTS BSCCO. Zaproponowano też nową konstrukcję wirnika z materiału HTS YBCO. Obliczono moment elektromagnetyczny wykorzystując metodę elementów skończonych.

12

Effectivity of piezoelectric transition elements in modelling of electro-mechanical systems

Zielińska Magdalena, Zboiński Grzegorz

Agricultural Engineering

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2019

|

Vol. 23, No. 2

93--101

EN

The paper presents the coupled electro-mechanical problem. In the numerical analysis of the issue, piezoelectric solid-to-shell transition elements were applied. They combine three-dimensional or hierarchical shell piezoelectric elements with piezoelectric first order elements. The mentioned first order of the element refers to the field of transversal displacements of an element. The mechanical field of the discussed piezoelectric elements may correspond to: the model of three-dimensional theory of elasticity, hierarchical shell models of higher orders or the first order shell model. The electrical field of the potential may be modelled with hierarchical dielectric first order models or higher in transverse direction or with a three-dimensional theory. Effectiveness of modification of algorithms of classical piezoelectric elements was assessed in this paper. To perform such an assessment, curves of convergence of hp method in model tasks are presented. Curves obtained with the use of classical and modified piezoelectric transition elements were set and compared.

PL

Praca dotyczy sprzężonego problemu elektro-mechanicznego. W analizie numerycznej zagadnienia zastosowane zostały piezoelektryczne elementy przejściowe o charakterze bryłowopowłokowym. Łączą one ze sobą trójwymiarowe (lub hierarchiczne powłokowe) elementy piezoelektryczne z elementami piezoelektrycznymi pierwszego rzędu. Wspomniany pierwszy rząd elementu odnosi się do pola przemieszczeń poprzecznych elementu. Pole mechaniczne omawianych elementów piezoelektrycznych może odpowiadać modelom trójwymiarowej teorii sprężystości, hierarchicznym modelom powłokowym wyższych rzędów lub modelowi powłokowemu pierwszego rzędu. Elektryczne pole potencjału modelowane może być za pomocą hierarchicznych modeli dielektrycznych rzędu pierwszego lub wyższych w kierunku poprzecznym lub teorią trójwymiarową. W niniejszej pracy dokonana została ocena efektywności modyfikacji wprowadzonych do algorytmów klasycznych elementów piezoelektrycznych. W celu takiej oceny przedstawione są krzywe zbieżności metody hp w zadaniach modelowych. Zestawione ze sobą i porównane zostały krzywe uzyskane z wykorzystaniem klasycznych i zmodyfikowanych, piezoelektrycznych elementów przejściowych.

13

Violin bridge vibrations - FEM

Kabała A., Niewczyk B., Gapiński B.

Vibrations in Physical Systems

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2018

|

Vol. 29

art. no. 2018021

EN

Violin bridge transmits vibration of the strings on the violin body. In numerous publications, the feet of the bridge are often glued to a rigid surface. In this paper the authors present a model of the bridge based on springs. The movement of the top of the bridge is partially limited by the violin strings. This movement limitation is modelled as an additional spring. Furthermore, it is possible to introduce a model of sound post. The material of the bridge (maple) is modelled as anisotropic.

14

On the influence of arching and material on the vibration of a shell - towards understanding the soloist violin

Jansson E. V., Kabała A.

Vibrations in Physical Systems

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2018

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Vol. 29

art. no. 2018027

EN

A study of the results of FEM simulations of plate and shell models are presented to reference of a violin vibrations problems. The influence of arching, variable thickness and damping was considered. ABAQUS/Explicit procedure of “Dynamic Explicit” was used in the simulation. Anisotropy in the material properties (spruce) was considered (9 elastic constants).

15

Metody badania zjawisk zachodzących podczas cięcia strugą wodno-ścierną pod kątem prognozowania głębokości i topografii powierzchni obrobionej. Cz. 1

Wala T.

Stal, Metale & Nowe Technologie

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2018

|

nr 9-10

63--67

PL

Artykuł przedstawia zrealizowane metody badawcze w odniesieniu do prognozowania głębokości oraz profilu chropowatości powierzchni po cięciu wysokociśnieniową strugą wodno-ścierną. W pierwszej części przedstawiono metodykę modelowania interakcji strugi tnącej z powierzchnią przedmiotu dla wybranych materiałów metodą elementów skończonych.

EN

The paper presents the testing methods used for the prognosis of the depth and roughness profile of a surface after abrasive waterjet cutting. The first part describes the methodology of modeling the interaction of the abrasive waterjet with the surface for selected materials using the finite element method.

16

Metody badania zjawisk zachodzących podczas cięcia strugą wodno-ścierną pod kątem prognozowania głębokości i topografii powierzchni obrobionej. Cz. 2

Wala T.

Stal, Metale & Nowe Technologie

|

2018

|

nr 11-12

44--46

PL

W drugiej części artykułu zamieszczono wyniki badań drgań głowicy podczas procesu cięcia, na podstawie których dokonano próby wykazania bezpośredniego związku pomiędzy drganiami a chropowatością powierzchni.

EN

In the second part of the article, the results of the cutter head vibration tests during the cutting process is presented, based on which the direct relationship between vibrations and the roughness of the surface has been demonstrated.

17

Application of additional grounded wires in high voltage overhead power lines to reduce the intensity of electric field generated by phase wires

Gumiela J., Sztafrowski D.

Przegląd Elektrotechniczny

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2018

|

R. 94, nr 3

159--161

EN

To minimize interference with the environment it is important to make every effort already at the design stage to spare the trouble associated with additional investment later on. Due to the value of land in urban areas, it is beneficial to take necessary measures to reduce the width of the impact zone and optimize the management of these lands. Possible variants of this assumption were analysed on the example of the existing 110 kV line.

PL

W celu ograniczenia natężenia pola elektrycznego w środowisku warto już na etapie projektowania obiektów elektroenergetycznych dołożyć wszelkich starań minimalizujących uciążliwość nowej inwestycji. W odpowiednich aktach prawnych zostały określone graniczne wartości m.in. pola elektrycznego co determinuje szerokość tzw. pasa technologicznego oraz ograniczenia w zagospodarowaniu sąsiadujących terenów. Na przykładzie istniejącej linii 110 kV poddano analizie możliwe warianty realizacji tego założenia.

18

Analiza technicznych możliwości ograniczania zjawiska ulotu elektrycznego zrealizowana na podstawie cyfrowej identyfikacji natężenia pola elektrycznego w otoczeniu przewodów roboczych elektroenergetycznych linii WN

Sztafrowski D., Gumiela J.

Przegląd Elektrotechniczny

|

2018

|

R. 94, nr 1

113--116

PL

Jednym ze zjawisk towarzyszących pracy linii elektroenergetycznych wysokich napięć jest ulot elektryczny. Ulot odpowiada m.in. za straty elektryczne, powstawanie ozonu oraz związków chemicznych powodujących przyspieszoną korozję przewodów napowietrznej linii elektroenergetycznej. Na podstawie przeprowadzonych analiz w artykule wskazano na możliwości ograniczenia występowania zjawiska ulotu co korzystnie wpływa na trwałość przewodów fazowych oraz redukcję zmniejszenie strat związanych z przesyłem energii elektrycznej.

EN

One of the phenomena accompanying the operation of high voltage power lines is the electric corona effect. Corona discharge is responsible among others for electrical losses, formation of ozone and the chemical compounds leading to accelerated corrosion of wires of the overhead power lines. On the basis of the analysis in the article indicated the possibility of limiting the occurrence of the corona effect what is beneficial to the durability of the phase wires, and reduction of losses in transmission of electrical power.

19

Simulation of the process of metal hardness measurement by the rockwell method

Berczyński S., Grochała D., Grządziel Z.

New Trends in Production Engineering

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2018

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Vol. 1, Iss. 1

647-654

EN

The article presents a simulation of metal hardness determination by the Rockwell method. The authors describe a physical model of an indenter and the examined sample built by means of the Nastran FX 2010 program using the finite elements method. The modelling included subsequent stages of indenter loads that follow the procedure used in the method. The verifying calculations were made for the results of C45 steel hardness of approx. 20 HRC. Two methods of hardness measurements were analyzed. A diamond cone was used as an indenting tool in one method, a steel ball in the other. As a result of calculations, spatial maps of elastic and plastic strains and stresses were obtained throughout the process. The hardness results obtained from computer simulations and those from experiments involving C45 steel are similar. metal hardness, Rockwell method, finite elements method, Nastran FX 2010, elastic strains twardość metalu, metoda Rockwella, metoda elementów skończonych, Nastran FX 2010, odkształcenia sprężyste

20

Wpływ kształtu żeber na ich odwzorowanie w procesie tłoczenia stemplem elastycznym

Krakowski M., Bartnicki J.

Mechanik

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2018

|

R. 91, nr 12

1078--1080

PL

Przybliżono problematykę kształtowania wyrobów z blach za pomocą stempli elastycznych. Wykonano obliczenia numeryczne wybranego kształtu żeber planowanej do wykonania wytłoczki. Ich celem było ustalenie parametrów technologicznych procesu. Zmiana wysokości żebra oraz promieni zaokrągleń wytłoczki pozwoliła na ustalenie ograniczeń tego procesu w odniesieniu do planowanej geometrii kształtowanego wyrobu. Prace badawcze kontynuowano w oparciu o narzędzia wykonywane metodą druku 3D. W ten sposób weryfikowano doświadczalnie wyniki symulacji.

EN

The paper deals with the drawing process by means of elastic tools. Numerical analysis of this kind of sheet metal forming were realized for chosen rib shapes. Changes of radius and rib height values were useful for technological parameters verification taking into consideration planned final parts geometry. In this work the comparison between numerical analysis results and laboratory research using 3D printing technology are presented.