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Number of results: 67
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Abstract

The present paper is dedicated to presentation and energy verification of the methods of stabilization the strain energy by penalty coefficients. Verification of the methods is based on the consistency and ellipticity conditions to be satisfied by the finite elements. Three methods of stabilization are discussed. The first does not satisfy the above requirements. The second is consistent but cannot eliminate parasitic energy terms. The third method, proposed by the author, is based on the decomposition of the element stiffness matrix. The method can help to eliminate locking of the finite elements. For two-noded beam element with linear shape functions and exact integration a stabilized free of locking (and elliptical) element is received (equivalent to reduced integration element). Two plate finite elements are analyzed: four-noded rectangular element and DSG triangle. A new method of stabilization with the use of four independent parameters is proposed. The finite elements with this kind of stabilization satisfy the consistency condition. In the rectangular element it was not possible to eliminate one parasitic term of energy which appears during the procedure. For DSG triangle all parasitic terms of energy are eliminated. The penalty coefficients depends on the geometry of the triangle.

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Authors and Affiliations

W. Gilewski
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Abstract

The paper presents an analysis of the effect of shape of primary silicon crystals on the sizes of stresses and deformations in a surface layer

of A390.0 alloy by Finite Elements Method (FEM). Analysis of stereological characteristics of the studied alloy, performed based on a

quantitative metallographic analysis in combination with a statistical analysis, was used for this purpose. The presented simulation tests

showed not only the deposition depth of maximum stresses and strains, but also allowed for determining the aforementioned values

depending on the shape of the silicon crystals. The studied material is intended for pistons of internal combustion engines, therefore the

analysis of the surface layer corresponded to conditions during friction in a piston-cylinder system of an internal combustion engine having

power of up to 100 kW. The obtained results showed important differences in the values of stresses and strains up to 15% between various

shape of the silicon crystals. Crystals with sharp edges caused higher stresses and deformation locally than those with rounded shapes.

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Authors and Affiliations

R. Wieszała
J. Piątkowski
H. Bąkowski
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Abstract

This paper presents the possibility to apply numerical simulation in static analysis of reinforcedconcrete structure strengthened with carbon fibre reinforced polymer composite strips (CFRP).Reinforced concrete beams, with strengthening in form values CFRP made of carbon fibres andepoxy resin, featuring various width, as well as non-strengthened bent beams, were analysed. Thesimply supported beams arranged in a free support scheme were subjected to two concentratedforces within full range of loading (until collapse). The numerical analysis was performed throughapplication of the Finite Elements Method (FEM), and the calculation model applied took intoaccount the geometric and physical nonlinearity. The problem was solved by application of thequasi-staticstrategy method of calculations using ABAQUS software. While analysing the results,we focused on the run of changes in structure displacement and development of material damage,up to the point of destruction of the beam.

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Authors and Affiliations

W. Głodkowska
M. Ruchwa
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Abstract

Magnetic properties of silicon iron electrical steel are determined by using standardized measurement setups and distinct excitation parameters. Characteristic values for magnetic loss and magnetization are used to select the most appropriate material for its application. This approach is not sufficient, because of the complex material behavior inside electrical machines, which can result in possible discrepancies between estimated and actual machine behavior. The materials’ anisotropy can be one of the problems why simulation and measurement are not in good accordance.With the help of a rotational single sheet tester, the magnetic material can be tested under application relevant field distribution. Thereby, additional effects of hysteresis and anisotropy can be characterized for detailed modelling and simulation.

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Authors and Affiliations

Gregor Bavendiek
Nora Leuning
ORCID: ORCID
Fabian Müller
Benedikt Schauerte
ORCID: ORCID
Andreas Thul
Kay Hameyer
ORCID: ORCID
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Abstract

This article presents a computer simulation carried out in the Solidworks environment, the bumper beam of a passenger car was tested. The simulation took into account the influence of various aluminum alloys and the type of reinforcement in the crosssection of the beam on the strength of the entire element at the time of collision at different forces. The analysis provided answers in which places the accumulation of stresses occurs, and thus the places most exposed to destruction
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Authors and Affiliations

A. Śliwa
1
ORCID: ORCID
W. Mikołejko
1
ORCID: ORCID
M. Bonek
1
A. Dziwis
1
ORCID: ORCID

  1. Silesian University of Technology, Faculty of Mechanical Engineering, Institu e of Materials Engineering and Biomedical Sciences, 18A S. Konarskiego St r., 44-100 Gliwice, Poland
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Abstract

This paper presents a model of the capacitance and electrical properties of semiconductor lasers biased with modulated voltage. The model is based on the finite-element method (FEM), which is widely used in computer modelling and is a natural generalisation of a wellknown constant-voltage FEM electrical model. In principle, the model can be applied to any kind of device where inductance can be neglected. Here, it is applied to simulate the complex impedance and other high-frequency electrical properties of a vertical-cavity surface-emitting laser. These properties are very important for the application of such lasers in optical data transfer systems. The results show that both the diameter of the top mesa and the surface area of the top electrical contact have a strong impact on the performance of the laser. This impact is analysed as a function of the modulation frequency.
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Authors and Affiliations

Michał Wasiak
1
ORCID: ORCID
Robert P. Sarzała
1
ORCID: ORCID

  1. Institute of Physics, Lodz University of Technology, ul. Wólczańska 217/221, 93-005 Lodz, Poland
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Abstract

Underground mining extraction causes the displacement and changes of stress fields in the surrounding rock mass. The determination of the changes is extremely important when the mining activity takes place in the proximity of post-flotation tailing ponds, which may affect the stability of the tailing dams. The deterministic modeling based on principles of continuum mechanics with the use of numerical methods, e.g. finite element method (FEM) should be used in all problems of predicting rock mass displacements and changes of stress field, particularly in cases of complex geology and complex mining methods. The accuracy of FEM solutions depends mainly on the quality of geomechanical parameters of the geological strata. The parameters, e.g. young modulus of elasticity, may require verification through a comparison with measured surface deformations using geodetic methods. This paper presents application of FEM in predicting effects of underground mining on the surface displacements in the area of the KGHM safety pillar of the tailing pond of the OUOW Żelazny Most. The area has been affected by room and pillar mining with roof bending in the years 2008-2016 and will be further exposed to room-and-pillar extraction with hydraulic filling in the years 2017–2019.

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Authors and Affiliations

Ewa Warchała
Anna Szostak-Chrzanowski
Paweł Stefanek
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Abstract

Using perforated tube in exhaust mufflers is known to improve transmission loss (TL) by improving their sound pressure level (SPL) at the orifice. The perforated tube should affect the muffler performance analogous to a shell-and-tube heat exchanger. To the authors’ knowledge, there are few previous assessments reported in literature of the effects that the perforated tube configuration has on acoustic response and pressure drop predicted. The effects of (i) the perforated tube length, (ii) the diameter of tube holes, and (iii) flow through perforated tube were investigated. To assess the perforated tube effect on flow, the SOLIDWORKS 2017 based on Computational Fluid Dynamics (CFD) tool was utilized using real walls approach model with a surface roughness of 0.5 micrometres (AISI 316 cold rolled stainless steel sheet (ss) Ra = 0:5 μm). Perforated tube was found to cause back pressure which may increase SPL about 10%.
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Bibliography

1. Cui F., Wang Y., Cai R.C. (2014), Improving muffler performance using simulation-based design, [in:] INTER-NOISE and NOISE-CON Congress and Conference Proceedings, 249(7): 1190–1194.
2. Demir A., Çinar Ö.Y. (2009), Propagation of sound in an infinite two-part duct carrying mean flow inserted axially into a larger infinite duct with wall impedance discontinuity, ZAMM – Journal of Applied Mathematics and Mechanics, 89(6): 454–465, doi: 10.1002/zamm.200800145.
3. Elsayed A., Bastien C., Jones S., Christensen J., Medina H., Kassem H. (2017), Investigation of baffle configuration effect on the performance of exhaust mufflers, Case Studies in Thermal Engineering, 10: 86–94, doi: 10.1016/j.csite.2017.03.006.
4. Ferziger J.H., Peric M. (2002), Computational Methods for Fluid Dynamics, 3rd ed., Springer, doi: 10.1007/978-3-642-56026-2.
5. Lee I., Selamet A. (2006), Impact of perforation impedance on the transmission loss of reactive and dissipative silencers, The Journal of the Acoustical Society of America, 120(6): 3706–3713, doi: 10.1121/1.2359703.
6. Mohamad B. (2019), Design and optimization of vehicle muffler using the Ffowcs Williams and Hawkings model, Machine Design, 11(3): 101–106, doi: 10.24867/MD.11.2019.3.101-106.
7. Mohamad B., Karoly J., Zelentsov A., Amroune S. (2020), A hybrid method technique for design and optimization of Formula race car exhaust muffler, International Review of Applied Sciences and Engineering, 11(2): 174–180, doi: 10.1556/1848.2020.20048.
8. Siano D. (2010), Three-dimensional/one-dimensional numerical correlation study of a three-pass perforated tube, Simulation Modelling Practice and Theory, 19(4): 1143–1153, doi: 10.1016/j.simpat.2010.04.005.
9. Sim H.J., Park S.G., Joe Y.G., Oh J.E. (2008), Design of the intake system for reducing the noise in the automobile using support vector regression, Journal of Mechanical Science and Technology, 22(6): 1121–1131, doi: 10.1007/s12206-008-0306-z.
10. Tiryakioglu B. (2020), Radiation of sound waves by a semi-infinite duct with outer lining and perforated end, Archives of Acoustics, 45(1): 77–84, doi: 10.24425/aoa.2020.132483.
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Authors and Affiliations

Barhm Mohamad
1
Jalics Karoly
1
Andrei Zelentsov
2
Salah Amroune
3

  1. Faculty of Mechanical Engineering and Informatics, University of Miskolc, Miskolc, Hungary
  2. Piston Engine Department, Bauman Moscow State Technical University, Moscow, Russia
  3. Université Mohamed Boudiaf, M’sila, Algérie
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Abstract

Numerical models allow structural characteristics to be obtained by solving mathematical formulations. The sound absorption capacity of a material can be acquired by numerically simulating an impedance tube and using the method governed by ISO 10534-2. This study presents a procedure of obtaining sound pressure using two microphones and as outline condition, at one end of the tube, the impedance of fiber samples extracted from the pseudostem of banana plants. The numerical methodology was conducted in the ANSYS® Workbench software. The sound absorption coefficient was obtained in the MATLAB® software using as input data the sound pressure captured in the microphones and applying the mathematical formulations exposed in this study. For the validation of the numerical model, the results were compared with the sound absorption coefficients of the fiber sample collected from an experimental procedure and also with the results of a microperforated panel developed by Maa (1998). According to the results, the methodology presented in this study showed effective results, since the largest absolute and relative errors were 0.001 and 3.162%, respectively.
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Bibliography

1. ASTM E1050:2019, Standard test method for impedance and absorption of acoustical materials using a tube, two microphones and a digital frequency analysis system.
2. ASTM E354:2003, Acoustics – measurement of sound absorption in a reverberation room.
3. Bóden H., Abom M. (1986), Influence of errors on the two-microphone method for measuring acoustic properties in ducts, The Journal of the Acoustical Society of America, 79(2): 541–549, doi: 10.1121/1.393542.
4. Ming-hui G., Qing-quan H., Jin-man W., Haipeng Y. (2010), The modeling and simulation analysis of wooden perforated panel absorption structure, Noise & Vibration Wordwide, 41(10): 72–75, doi: 10.1260/0957-4565.41.10.72.
5. Howard C.Q., Cazzolato B.S. (2014), Acoustic Analyses using MATLAB® and ANSYS®, Boca Raton: CRC Press, Taylor & Francis Group.
6. ISO 10534-1:1996, Acoustic – Determination of sound absorption coefficient and impedance in impedance tubes – Part 1: Method using standing wave ratio.
7. ISO 10534-2:1998, Acoustics – Determination of sound absorption coefficient and impedance in impedance tubes. Part 2: Transfer-function method.
8. ISO 354:2003, Measurement of sound absorption in a reverberant room.
9. Kinsler L.E., Frey A.R., Coppens A.B., Sanders J.V. (2000), Fundamentals of Acoustics, Hoboken: John Wiley & Sons, New York.
10. Lara L.T., Boaventura W.C., Pasqual A.M. (2016), Improving the estimated acoustic absorption curves in impedance tubes by using wavelet-based denoising methods, Congresso Iberoamericano de Acústica, Buenos Aires, Argentina, 22, 1–10.
11. Maa D.Y. (1998), Potential of microperforated panel absorber, The Journal of the Acoustical Society of America, 104(5): 2861–2866, doi: 10.1121/1.423870.
12. Rienstra S.W., Hirschberg A. (2014), An Introduction to Acoustics, Eindhoven University of Technology, Netherlands.
13. Silva G.C.C., Nunes M.A.A., Almeida Jr A.B., Lopes R.V. (2013), Acoustic design and construction of an impedance tube for experimental characterization of sound absorbed materials [in Portuguese: Projeto Acústico e Construção de um Tubo de Impedância para Caracterização Experimental de Materiais com Absorção Sonora], [in:] XVIII Congresso de Iniciação Científica da UnB, Brasília, Brazil.
14. Soriano H.L. (2009), Finite Elements – Formulation and Application in Static and Dynamic Structures [in Portuguese: Elementos Finitos – Formulação e Aplicação na Estática e Dinâmica das Estruturas], Rio de Janeiro: Editora Ciência Moderna Ltda.
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Authors and Affiliations

Cláudia Ohana Borges Mendes
1
Maria Alzira De Araújo Nunes
1

  1. Graduate Program in Engineering Materials Integrity, University of Brasília-UnB, College UnB Gama-FGA Área Especial de Indústria Projeção A, Setor Leste, CEP:72.444-240, Gama, Distrito Federal, Brazil
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Abstract

This article presents a comparison of test results from two models of anti-vibration systems (I and II) made employing MJF 3D printing technology and two different materials. The research included laboratory tests and numerical simulations, assuming a linear nature of the mechanical properties for the materials and models of structures. The aim of this research was to assess the consistency between laboratory test and numerical simulation results. In addition, evaluation of the suitability of using MJF technology to produce antivibration systems was conducted. During the laboratory tests, the response of the two models of structures to vibrations generated by an exciter was recorded using a high-speed camera. Subsequent image analysis was performed using the MOVIAS Neo software. The obtained values of vibration displacements and resonant frequencies were used to validate the numerical model created in the Simcenter Femap software. Relative differences between the values of resonant frequencies obtained experimentally and through simulations were determined. In the case of the structural model I, creating its numerical model without considering the nonlinearity of mechanical parameters was found to be unjustified. The comparison of the displacements determined during numerical simulations showed relative differences of less than 16% for both models in relation to the laboratory test results. This comparison result indicates a satisfactory accuracy in simulating this parameter. An assessment of the quality and accuracy of MJF technology-produced prints, led to the conclusion that due to the formation of internal stresses during the print creation, the use of “soft” materials in this technology is problematic.
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Authors and Affiliations

Piotr Kowalski
1
ORCID: ORCID
Adrian Alikowski
1
ORCID: ORCID

  1. Central Institute for Labour Protection – National Research InstituteWarsaw, Poland
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Abstract

This article presents a sequential model of the heating-remelting-cooling of steel samples based on the finite element method (FEM) and the smoothed particle hydrodynamics (SPH). The numerical implementation of the developed solution was completed as part of the original DEFFEM 3D package, being developed for over ten years, and is a dedicated tool to aid physical simulations performed with modern Gleeble thermo-mechanical simulators. Using the developed DEFFEM 3D software to aid physical simulations allows the number of costly tests to be minimized, and additional process information to be obtained, e.g. achieved local cooling rates at any point in the sample tested volume, or characteristics of temperature changes. The study was complemented by examples of simulation and experimental test results, indicating that the adopted model assumptions were correct. The developed solution is the basis for the development of DEFFEM 3D software aimed at developing a comprehensive numerical model allows the simulation of deformation of steel in semi solid state.

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Authors and Affiliations

Marcin Hojny
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Abstract

The paper demonstrates the potential of wavelet transform in a discrete form for structural damage localization. The efficiency of the method is tested through a series of numerical examples, where the real flat truss girder is simulated by a parameterized finite element model. The welded joints are introduced into the girder and classic code loads are applied. The static vertical deflections and rotation angles of steel truss structure are taken into consideration, structural response signals are computed at discrete points uniformly distributed along the upper or lower chord. Signal decomposition is performed according to the Mallat pyramid algorithm. The performed analyses proved that the application of DWT to decompose structural response signals is very effective in determining the location of the defect. Evident disturbances of the transformed signals, including high peaks, are expected as an indicator of the defect existence in the structure. The authors succeeded for the first time in the detection of breaking the weld in the truss node as well as proved that the defect can be located in the diagonals.
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Authors and Affiliations

Anna Knitter-Piątkowska
1
ORCID: ORCID
Olga Kawa
1
Michał Jan Guminiak
1

  1. Poznan University of Technology, Institute of Structural Analysis, Poland
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Abstract

The actual load-bearing capacity of elements of a building system can be calculated by dynamic parameters, in particular by resonant frequency and compliance. The prerequisites for solving such a problem by the finite element method (FEM) are presented in the article. First, modern vibration tests demonstrate high accuracy in determination of these parameters, which reflects reliability of the diagnosis. Secondly, most modern computational complexes do not include a functional for calculating the load-bearing capacity of an element according to the input values of resonance frequencies. Thirdly, FEM is the basis for development of software tools for automating the computation process. The article presents the method for calculating flexural stiffness and moment of inertia of a beam construction system by its own frequencies. The method includes calculation algorithm realizing the finite element method.

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Authors and Affiliations

A. Nesterenko
G. Stolpovskiy
M. Nesterenko
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Abstract

The main objective of this work is to present the results of numerical simulations of the landslide triggered by small excavation. In south-eastern Poland in 2019, during excavation for a gas pipeline (relatively small – maximal depth 2.7 m), a landslide was observed. Length of the landslide was about 80 m, width about 50 m, maximal depth 6.5 m. Excavation was partially buried. Observed cracks of the terrain surface were wide, up to 0.8 m. Stability of the landslide was analyzed using the proportional reduction of the soil strength parameters (c-fi reduction) algorithm with the use of ZSoil.PC Finite Element Method (FEM) system. Stability analysis of the slope before and after excavation was performed, together with analysis of the tendency of the landslide to propagate upwards. The obtained stability loss modes were compared with the results of the field observations and a good correlation was noticed. Hypothesis that a landslide was triggered by small excavation was proved (although reasonable margin of safety was obtained for state before excavation, stability factor SF = 1•60). Use of residual soil strength parameters (instead of peak ones) and activation of cut-off (no tension) condition are advised. Presented methodology is open and can be used in engineering practice.
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Authors and Affiliations

Michał Grodecki
1
ORCID: ORCID

  1. Cracow University of Technology, Civil Engineering Department, 24 Warszawska Str., 31-155 Cracow, Poland
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Abstract

A new method of creating constitutive model of masonry is reported in this work. The model is not an explicit orthotropic elastic-plastic one, but with an artificial neural network (ANN) giving an implicit constitutive function. It relates the new state of generalised stresses Σ n+1 with the old state Σ n and with an increment of generalised strains ΔE (plane-stress conditions are assumed). The first step is to run a strain- controlled homogenisation, repeatedly, on a three-dimensional finite element model of a periodic cell, with elastic-plastic models (Drucker–Prager) of the components; thus a set of paths is created in (Σ, ΔE) space. From these paths, a set of patterns is formed to train the ANN. A description of how to prepare these data and a discussion on ANN training issues are presented. Finally, the procedure based on trained ANN is put into a finite-element code as a constitutive function. This enables the analysis of arbitrarily large masonry systems. The approach is verified by comparing the results of the developed model basing on ANN with a direct (single-scale) one, which showed acceptable accuracy.
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Authors and Affiliations

Aleksander Urbański
1
ORCID: ORCID
Szymon Ligęza
2
ORCID: ORCID
Marcin Drabczyk
3
ORCID: ORCID

  1. Cracow University of Technology, Faculty of Civil Engineering, ul. Warszawska 24, 31-155, Kraków, Poland
  2. AGH University of Science and Technology, Faculty of Drilling, Oil and Gas (doctoral student), al. Mickiewicza 30, 30-059 Kraków, Poland
  3. Idealogic Ltd., ul. Kapelanka 26, 30-347 Kraków, Poland
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Abstract

Main goal of this paper is to present results of the numerical simulations of a real-scale gabion retaining wall tests. 4.5 m high wall was loaded and unloaded with water pressure, displacements of the crest of the wall were measured. Finite Element Method was used to simulate experiment and obtained results are compared with experimental ones. Usage of homogenized Coulomb-Mohr type continuum for gabions is proposed. Strength parameters of the model (cohesion and friction angle) are estimated on the base of large scale triaxial tests of the gabions and static tensile tests of the mesh. Influence of the “cut-off” condition on obtained results is analyzed. Elastic model for gabions is used for comparison of the results. Interface elements and truss joints between the gabions are used to simulate joints between gabions with limited strength. Good correlation between displacements obtained in experiment and numerical simulations was observed, especially in loading phase, so presented methodology of numerical modelling allows to model gabion retaining walls behavior close to the reality and could be used in engineering practice.
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Authors and Affiliations

Michał Grodecki
1
ORCID: ORCID

  1. PhD., Eng., Cracow University of Technology, Faculty of Civil Engineering, ul. Warszawska 24, 34-155 Cracow, Poland
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Abstract

This paper presents the results of laboratory testing and Finite Element Method (FEM) modelling of high-strength double-twisted steel hexagonal wire mesh used for constructing gabion cages, slope protection systems, rockfall protection barriers. Gabion cages, filled with soil (usually rock particles) are commonly used in civil engineering (for example, in order to form a retaining wall). Static tensile tests of single wire and double-twisted wire were performed. The stiffness and ultimate tensile strength were examined. Special attention was paid to the double-twist behaviour. The unloading tests were also performed and the range of elastic deformation of both single wire and double-twisted wire were determined. The obtained laboratory results (stress–strain relationships for single wire and double-twisted wire) were included in a numerical model of the repeatable cell of mesh (truss model). The simulation in both directions, parallel and perpendicular to the double twist, was performed. On the basis of the obtained load-strain relationship, an anisotropic membrane model for mesh was proposed and calibrated. The obtained value of tensile strength of the mesh (266 kN/m) is much higher than for other meshes known form literature (30–60 kN/m).
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Authors and Affiliations

Michał Grodecki
1
ORCID: ORCID
Krzysztof Nowak
1
ORCID: ORCID

  1. Cracow University of Technology, Civil Engineering Department, 24 Warszawska Str., 31-155 Cracow, Poland
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Abstract

This paper presents an analysis of natural vibrations of typical façade scaffolding. Three Finite Element Method models with different levels of accuracy of the real structure of the scaffolding representation were used. Modal analysis was carried out for each of these models. The obtained frequencies and mode shapes were compared with the results from the measurements performed on the full-scale scaffolding. The authors of the paper point out the difficulties arise while modelling such structures, and suggest ways to improve the accuracy of scaffolding computational models.

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Authors and Affiliations

P. Jamińska-Gadomska
J. Bęc
T. Lipecki
A. Robak
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Abstract

The accurate prediction of iron losses has become a prominent problem in electromagnetic machine design. The basis of all iron loss models is found in the spatial field-locus of the magnetic flux density (B) and magnetic field (H). In this paper the behavior of the measured BH-field-loci is considered in FEM simulation. For this purpose, a vector hysteresis model is parameterized based on the global measurements, which then can be used to reproduce the measurement system and obtain more detailed insights on the device and its local field distribution. The IEM has designed a rotary loss tester for electrical steel, which can apply arbitrary BH-field-loci occurring during electrical machine operation. Despite its simplicity, the proposed pragmatic analytical model for vector hysteresis provides very promising results.

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Authors and Affiliations

Fabian Müller
Gregor Bavendiek
Benedikt Schauerte
ORCID: ORCID
Kay Hameyer
ORCID: ORCID
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Abstract

In conventional finite element simulations, foil windings with thin foils and with a large number of turns require many mesh elements. This renders models quickly computationally infeasible. This paper uses a homogenized foil winding model and approximates the voltage distribution in the foil winding domain by globally supported polynomials. This way, the small-scale structure in the foil winding domain does not have to be resolved by the finite element mesh. The method is validated successfully for a stand-alone foil winding example and for a pot inductor example. Moreover, a transformer equipped with a foil winding at its primary side is simulated using a field-circuit coupled model.
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Authors and Affiliations

Jonas Bundschuh
1 2
ORCID: ORCID
Yvonne Späck-Leigsnering
1 2
ORCID: ORCID
Herbert De Gersem
1 2
ORCID: ORCID

  1. Institute for Accelerator Science and Electromagnetic Fields (TEMF) Technical University of Darmstadt Schloßgartenstraße 8, 64289 Darmstadt, Germany
  2. Graduate School of Excellence Computational Engineering Technical University of Darmstadt Dolivostraße 15, 64293 Darmstadt, Germany
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Abstract

Femoral fractures are frequent in adolescents and children, and most fractures occur within the centre of the bone, typically referred to as the femur shaft. Plate and screws are ideal fixation methods for femoral fractures close to the articular sur-faces. When using plates and screws, estimating the load on the plates and screws before starting treatment is important. The primary focus of this paper is the examination of fixation plates utilized in the treatment of femur bone fractures. The study employs the finite element method to conduct this analysis. Initial modelling of the femur bone is executed through the utilization of CATIA V5 software. Subsequently, the investigation transitions to the ANSYS R14.5 environment, where more in-depth analysis is carried out. The modelling of the fracture fixation plates is done on commercially available CAD software CATIA V5. The stress distribution of different biomaterials in the bone plate system is calculated when the system is subjected to compressive loads with varying healing times. Here we have used stainless steel (SS316-L), titanium alloy (Ti6Al4V) and magnesium alloy (AZ31). More focus was given to the magnesium alloy. Here a fracture gap of 1mm gap was taken for analysis. A comprehensive compressive force amounting to 750 N was applied to the bone-plate assembly during the simulation. This force magnitude corresponds to the approximate weight of an average human body.
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Authors and Affiliations

Pranjal Sarmah
1
Ravi Kumar
1
Amrit Thakur
1
Mohit Sharma
1
Surendra Kumar Yadav
2
Virendra Kumar
3
ORCID: ORCID

  1. Department of Mechanical Engineering, Dibrugarh University, Dibrugarh 786004, Assam, India
  2. Department of Mechanical Engineering, K. R. Mangalam University, Gurugram 122001, India
  3. Department of Mechanical Engineering, Harcourt Butler Technical University, Kanpur 208002, India
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Abstract

The paper presents kinetic fatigue crack growth curve for IOHNAP steel, which is verified experimentally. An energy approach based on the M-integral range is shown. The tests have been carried out on plane specimens With notches under tension-compression for three values of stress ratio R. The J-integral is calculated analytically and by the finite element method. A relationship for the description of the whole kinetic crack growth curve including J-integral is presented. It is shown that at the constant loading and the change of stress ratio R from - 1 to O the fatigue crack growth rate increases. A relationship is proposed in the paper for description of the kinetic crack growth curve. It gives results that are consistent with experimental ones and those obtained with the use of the finite element method (FEM).
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Authors and Affiliations

Dariusz Rozumek
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Abstract

The multi-phase permanent-magnet machines with a fractional-slot concentrated-winding (FSCW) are a suitable choice for certain purposes like aircraft, marine, and electric vehicles, because of the fault tolerance and high power density capability. The paper aims to design, optimize and prototype a five-phase fractional-slot concentrated-winding surface-mounted permanent-magnet motor. To optimize the designed multi-phase motor a multi-objective optimization technique based on the genetic algorithm method is applied. The machine design objectives are to maximize torque density of the motor and maximize efficiency then to determine the best choice of the designed machine parameters. Then, the two-dimensional Finite Element Method (2D-FEM) is employed to verify the performance of the optimized machine. Finally, the optimized machine is prototyped. The paper found that the results of the prototyped machine validate the results of theatrical analyses of the machine and accurate consideration of the parameters improved the acting of the machine.

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Authors and Affiliations

Amir Nekoubin
Jafar Soltani
Milad Dowlatshah

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