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Engineering Analysis Application in Furniture Making : Deformation – Equivalent Stress

Seker Sedanur, Koc Kucuk Huseyin

Drewno : prace naukowe, doniesienia, komunikaty

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2023

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Vol. 66, nr 211

Art. no. 1644-3985.406.07

EN

The deformation of furniture units plays a significant role in their effective and efficient way of use during the overall service life. Accurate information on the deformation of different types of furniture members can be determined and evaluated by current testing methods. However, this will not only be expensive but also destructive. Therefore, the objectives of this study were to obtain initial data to predict the types and magnitudes of deformation which take place in various furniture works due to certain stress distribution. Such predictions were carried out by employing engineering analysis within the scope of the statistical approach. AutoCAD and SolidWorks software were used to design the furniture while the ANSYS finite element program route was employed for engineering analysis in this work. The joint types and stresses were applied as follows: dowel type joints having an equivalent stress level ranging from 0.20-0.96 MPa and a deformation level ranging from 0.0010.82 mm; mortise and tenon joints having an equivalent stress level ranging from 0.17-2.68 MPa, deformation level ranging from 0.02-0.17 mm. Minifix type joints having an equivalent stress level ranging from 0.07-17.6 MPa, and a deformation level ranging from 0.03-1.42 mm. It appears that the engineering tools used in this study can successfully be applied to determine the deformation behaviors of furniture units.

2

Numerical investigation on the vibration reduction of rotating shaft using different groove shapes of tilt bearing

Abbood Ahmed Imad, Abdulla Fadhel Abbas

Diagnostyka

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2023

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Vol. 24, No. 3

art. no. 2023304

EN

Vibration control is very important for high-speed rotors. Oil film damping is considered an effective vibration-damping method, especially for long shafts in gas turbines, ships, and other high-speed rotating equipment. The existing groove in the internal surface of the tilt bearing increases the amount of oil that flows through the bearing; this is more effective in suppressing the vibration of the rotor system carried by the plain bearing. In order to suppress the vibration of the rotor system, which is supported by sliding bearings, a different groove-shaped oil flow (GSOF) is studied and analysed in this paper. A different shape of grooves in bearings was set up and measured to study the vibration-damping effect of the flow oil shape with GSOF. ANSYS software presents significant benefits to engage Fluent for oil flow with Transient structural for vibration measurements. This paper uses these terms to perform the simulation numerically to explore the groove-shaped damper's damping effect under the rotor system. The study identified three enhancements of vibration and settling time. First, the circular groove showed a 35.71% reduction in amplitude and 10% increase in stilling time; the next one is the circular groove which reduced the amplitude by 42.85% and the settling time by 0%. The third modification was the inclined groove which reduced the amplitude by 42.85% and the settling time by 12%. The last one was the triple-inclined groove, which reduced the amplitude and settling time by 57.14% and 20%, respectively.

3

Determination of the Geometric Properties of a Jet Engine Fan Blades Based on Modal Vibration Testing

Osiewicz Maciej, Cieślak Sławomir, Bielecki Marcin

Transactions on Aerospace Research

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2022

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Nr 3 (268)

56--74

EN

The article presents an experimental method of determining the geometric properties of jet engine rotor airfoils based on modal vibration testing. The procedure is based on adjusting the results of analytical calculations to the laboratory outcomes. Experimental tests were carried out on a set of 20 jet engine fan blades made of AL7022-T6 aluminium alloy. Each blade differed in weight and geometric dimensions within the accepted design tolerance. Numerical analysis of five airfoils that differed in thickness was performed. Modal vibration test results were summarised and compared with the results obtained by the numerical method. The comparison revealed a high similarity of the frequency and form of vibrations acquired by numerical simulation for each of the blades in relation to the executed vibration testing. Based on the verification of the theoretical model with the results obtained through experimental testing, conclusions were drawn about the object’s dynamic behaviour and its technological quality and geometric properties, whereby each of airfoil was probably thinned.

4

Influence of form defect on the mechanical behavior and stress intensity factor of shrink-fitted thick-walled cylinders

Boutoutaou Hamid, Chebbab Brahim, Belmessous Abdelmounaime

International Journal of Applied Mechanics and Engineering

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2022

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Vol. 27, no. 4

40--51

EN

In this research work, the finite element software, ABAQUS is used to study by simulations the influence of form defect on mechanical behavior of a shrink-fitted assembly presenting internal radial cracks. Under the action of contact pressure induced by the tightening between two cylinders, these cracks resulting from incorrect assembly operations or materials elaboration defect, can be harmful to the assembly. Various simulations were carried out in two modeling cases, taking into account the geometric parameters of defect (amplitude Df), of cylinders (thickness t) and of cracks (length a, ratio a/t). Another important parameter such as the tightening was also considered in the modeling. The first modeling relates to the case with defect, external cylinder presents an oval (elliptical) form defect and internal radial cracks. The other concerns the perfect equivalent case (without form defect). The comparison of results obtained by two models shows that form defect modifies the uniformity of equivalent stresses distribution in cylinders and increases the value of stress intensity factor (SIF) KI in cracks. Defect amplitude and tightening significantly influence the value of equivalent stress and that of stress intensity factor (SIF) KI.

5

On the fully discrete approximations of the MGT two-temperatures thermoelastic problem

Baldonedo J., Fernández J. R., Quintanilla R.

Archives of Mechanics

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2022

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Vol. 74, nr 5

391--407

EN

We consider a one-dimensional two-temperatures thermoelastic model. The corresponding variational problem leads to a coupled system which is written in terms of the mechanical velocity, the temperature speed and the inductive temperature. An existence and uniqueness result is recalled. Then, fully discrete approximations are introduced by using the finite element method and the implicit Euler scheme. A priori error estimates are proved and the linear convergence of the approximations is deduced under suitable additional regularity conditions. Finally, some numerical simulations are shown to demonstrate the accuracy of the proposed algorithm and the behavior of the discrete energy.

6

The trapezoidal finite element in absolute coordinates for dynamic modeling of automotive tire and air spring bellows. Part 1: equations of motion

Pogorelov Dmitry, Rodikov Alexander

Transport Problems

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2021

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T. 16, z. 2

141--152

EN

Equations of motion of a finite element in absolute coordinates including mass matrix, generalized inertia and internal forces are derived. A trapezoidal element for dynamic models of flexible shells in the shape of surface of revolution is considered. The element can be used for modeling dynamics of automotive tire and air spring bellows and some other flexible elements of transport systems undergoing large elastic deflections.

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The trapezoidal finite element in absolute coordinates for dynamic modeling of automotive tire and air spring bellows. Part II: verification

Pogorelov Dmitry, Rodikov Alexander

Transport Problems

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2021

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T. 16, z. 3

5--16

EN

The second part of the paper includes numerical tests verifying equations of motion of flexible bodies in absolute coordinates with rectangle and isosceles trapezoid finite elements. The equations are formulated in the first part of the paper. The verification is based on three types of problems: calculation of natural frequencies and modes, evaluation of buckling, and computation of large static and dynamic deflections of flexible bodies. Tests show good agreement with the theoretical results and the results obtained by other authors.

8

Fatigue tests and numerical analyses of the PAWO autonomous electric vehicle

Podkowski Krzysztof, Okruch Łukasz

Archiwum Motoryzacji

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2021

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Vol. 93, nr 3

39--58

EN

The following article presents fatigue testing and FEM numerical analysis of an autonomous electric vehicle, PAWO autonomous operational support platform. The purpose of the study, which was carried out in the ŁUKASIEWICZ – Automotive Industry Institute, was to verify the structure of the platform by forcing in three axes on the position: a table with six degrees of freedom "MAST", as well as conducting fatigue numerical analyses, allowing to determine places critical for fatigue endurance. This will be the starting point for the modification of the structure, and also will allow you to identify places that you need to pay attention to during tests and subsequent operation. The results of these tests allow us to determine critical places due to fatigue strength and possible intervention before starting field tests with a complete vehicle, as well as to detect places that should be noted during tests, inspections and tests, and in development versions of the vehicle.

9

Operating limits study based on Finite Elements of a Brushless Doubly-fed Induction Machine

Nezzari Indihir, Kessal Abdelhalim

Journal of Power Technologies

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2020

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Vol. 100, nr 1

14--20

EN

The Brushless Doubly-fed Induction Machine (BDFIM) is a new topology machine proposed for the generation of electrical energy at variable speed. The stator of this machine has two independent windings with diﬀerent numbers of poles (power winding and control winding). Its functioning is conditioned by certain physical constraints, i.e., the relation between the speed of the rotor, the polarities of the two windings and their frequencies. We have developed in this paper a ﬁnite element model to study and verify the operating limits of the BDFIM (2.2 Kw and 1/3 pairs of poles) on ﬂux2d.

10

Phase field modeling of cyclic fatigue crack growth under mixed mode loading

Schreiber Christoph, Kuhn Charlotte, Müller Ralf

Computer Methods in Materials Science

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2019

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Vol. 19, No. 2

50--56

EN

For the numerical handling of nucleation and extension of cracks within different materials, phase field modeling of fracture was shown to be a very beneficial technique in the past decade. Within numerous studies the framework was successfully applied even to complex crack problems. However, a phenomenon, which has not been much in the focus of research in terms of phase field modeling, is cyclic fatigue crack growth. Within technical developments this phenomenon is crucial as it has been found to be the source of several devastating accidents in the past. Within this work we introduce a phase field model capable of capturing fatigue crack growth under unidirectional as well as mixed mode loading. The driving force of the fatigue mechanism is controlled by cyclic damage evaluated from Miner's rule, a very famous and robust phenomenological law within fatigue simulations. Among the prediction of realistic crack growth curves, the accuracy of the model is verified by comparison with analytic results regarding the crack growth direction.

PL

W pracy wykazano, że w ostatnim dziesięcioleciu model pola faz okazał się efektywnym narzędziem do opisu zarodkowania i wzrostu pęknięć w różnych materiałach. Wielu badaczy skutecznie zastosowało ten model nawet do złożonych warunków obciążenia. Z drugiej strony problem wzrostu pęknięć w warunkach cyklicznych obciążeń zmęczeniowych nie był dotąd dogłębnie analizowany. To zjawisko było przyczyną wielu katastrof w przeszłości i stąd zasługuje na szczególną uwagę. W niniejszej pracy przedstawiono model pola faz pozwalający na opis wzrostu pęknięcia zarówno przy jednoosiowym jak i złożonym charakterze obciążeń. Siła pędna mechanizmu pękania jest kontrolowana przez cykliczne zniszczenie wyznaczane z reguły Minera, która jest znanym i skutecznym prawem stosowanych w modelowaniu pękania. Poza przewidywaniem realiztycznych krzywych pękania, przeprowadzono weryfikację modelu poprzez porównanie z wynikami analitycznymi dla przewidywania kierunku wzrostu pęknięcia.

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Convergence Analysis of Finite Element Approach to Classical Approach for Analysis of Plates in Bending

Niyonyungu Ferdinand, Karangwa Jules

Advances in Science and Technology. Research Journal

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2019

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Vol. 13, no 4

170--180

EN

Classical approach is a popular method used in the analysis of structures including bending plates, but these plates can have highly irregular geometry and contain holes or may be subjected to loading irregularity. Hence, the analysis is further complicated and the classical approaches are not valid. Thus, the Finite Element Method is used to control the accuracy and it is needed for more difficult problems. In the present study Fourier series theory as classical approach and finite element method of analysis were discussed and the numerical examples of a simply supported and fixed supported square steel plate were used to compare them. The results obtained with general public software LISA that uses FEM was plotted according to the element types, both quadrangular and triangular. Their convergence was verified with the values obtained from classical approach to validate the results of FEM from LISA. The results showed the conformity with the existing theories that the greater discretization the more the reality is approached. The convergence error of 5% was taken as the maximum for the element types and meshes to be used for highly sophisticated plate systems. The ratios of element size to the size of the whole square plate to be used for general cases of square plate dimensions were established.

12

On consistent nonlinear analysis of soil-structure interaction problems

Truty A.

Studia Geotechnica et Mechanica

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2018

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Vol. 40, nr 2

86--95

EN

Nonlinear soil-linear structure computational strategy is commonly accepted in the community of geotechnical engineers using advanced finite element software for solving complex soil-structure interaction problems. However, further design procedure of the structural elements is carried out using increased values of the computed elastic stress resultants. It is absolutely not clear whether this method is conservative and, therefore, whether safe or not. To tackle this problem, a fully consistent nonlinear analysis of a deep excavation protected by the diaphragm wall is analysed here. The subsoil is modelled using the Hardening Soil model, while reinforced concrete is modelled using the modified Lee-Fenves model enhanced by the Eurocode 2 (EC2)-compatible creep module, developed by the author. It is shown that the commonly used nonlinear soil-linear structure computational strategy may yield insufficient amount of reinforcement from the ultimate limit state (ULS) and serviceability limit state (SLS) points of view. A consistent and conservative method of combining fully nonlinear analysis and the rules imposed by the EC2 is proposed.

13

Determination of stress-strain state of reinforced slabs from non-linear material taking into account the influence of aggressive environment

Anatolyevich Treschev A., Valeryevich Bashkatov A., Grigoryevich Telichko V., Anatolyevich Bobryshev A., Nurgaleevich Shafigullin L.

Przegląd Naukowy Inżynieria i Kształtowanie Środowiska

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2018

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Vol. 28, No. 4

488--503

EN

In this article, the construction of finite-elemental model of definition of stress-strain state of reinforced concrete plates in conditions of active deformation and simple loading in combination with long-term influence of chloride-containing operating environment. Non-linear behavior of concrete is simulated based on the determining relations proposed by Treschev, cracking and plastic deformations in armature are taken into account. The impact of the aggressive environment is taken into account in accordance with the model proposed by Petrov and Penina. In the article all basic correlations of finite elements method in convenient for software realization on a computer are given. As the object of research for this article is a concrete plate reinforced with steel reinforcement in a stretched area, which is under the joint influence of mechanical load and aggressive chloride-containing environment on the protective polymer–concrete layer. The load was taken evenly distributed across the entire slab area. At the solution of this problem the non-linear sensitivity of the basic material (concrete) to the type of the tense condition, plastic deformations in armature, degradation of a protective concrete at influence of external aggressive environment are taken into account. In the article some especially characteristic results of mathematical modeling of the specified model problem are given. The obtained results of joint influence on the plate of mechanical load and aggressive environment are analyzed.

14

Geomechanics of interference between the operation modes of mine working support elements at their loading

Bondarenko V., Kovalevska I., Symanovych G., Sotskov V., Barabash M.

Mining Science

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2018

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Vol. 25

219--235

EN

The problem has been studied of reducing the materials consumption of a combined support in extraction mine workings and increasing their stability in a zone of stope works influence when reused mining of flat-lying coal seams at adjacent mining site. The mechanism has been developed of rock pressure manifestation in the vicinity of mine working and the loading of its support elements on the basis of the following key positions: the formation of zones of unloading and increased rock pressure around the mine working; the formation of areas of weakened and broken rocks, their interaction with support and holistic rock massif; development of stratification along the planes of weakening by thickness of a lithological variety and along the planes of bedding the adjacent lithotypes; partitioning of rock layer into blocks by fractures, by perpendicular planes of weakening and bedding planes, and other factors. The specific tasks have been solved by the finite element method according to the four-parameter spatial optimization scheme of the support interaction with a rock massif. The patterns have been determined of connection between the rational operation modes of mine working support elements and basic geomechanical factors, affecting significantly on the loading of these elements, as well as their interaction with different deformation and force characteristics.

15

Analysis of mechanical structures using plate finite element method under different boundary conditions

Hamrit F., Necib B.

Diagnostyka

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2018

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Vol. 19, No. 2

3--9

EN

The mechanical discrete or continuum structures are actually of great importance in the application field of contemporary modern industry. However, during their life time these structures are often subjected to considerable external stresses or to high amplitudes of vibrations which can cause them large deformations and internal stresses which can cause them internal cracking or even their total destruction. In order to avoid these types of problems, the concept of static and dynamic analysis of these structures is recommended, and due to the complexity of their shape and size, the finite element method is the most used. The latter is currently recognized as a very powerful technique for the static and dynamic analysis of discrete or continuous structures of complicated form applied in the field of mechanics, aeronautics, civil engineering, maritime or robotics. Consequently, the calculation and dimensioning of these mechanical systems by the finite element method plays an important role at the service of the industry for possible sizing and prediction of their lifetime. Our work consists of static and dynamic analysis of two-dimensional discrete and continuous mechanical systems using the finite element method based on the main elements of bars, beams and plates, under the effect of external excitations with different boundary conditions. The discrete structures considered are two-dimensional in metallic framework interconnected to the nodes by welding, riveting or bolted under various boundary conditions. Their elements are modeled comparatively by bar elements and beam elements, while for continuous structures the elements are rectangular thin plates with different boundary conditions. The excitation forces are based on periodic, random or impulsive forces and a numerical solution by development of a program to describe the behavior of these structures is realized. The mass and stiffness matrices of all the structures are determined respectively by assembling the bars, beam and plate elements based on the kinetic and deformation energy for each element. The displacements, the node reactions and the axial forces in all the elements as well as the transverse stresses and the eigenvalues of the structures under different boundary conditions were also calculated and good results were obtained compared to those obtained using other software already existing. In fact, analysis using the finite element method will allow the proper dimensioning and design of complex industrial mechanical structures according to different boundary conditions, their internal loading and their vibratory level.

16

Modelowanie wód podziemnych na terenach górniczych z wykorzystaniem oprogramowania FEFLOW

Sitek S.

Przegląd Geologiczny

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2017

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Vol. 65, nr 11/3

1451--1459

EN

Development of groundwater flow, and solute and heat transport models for underground and open-pit mining areas is a challenging and very complex issue. Despite the fact, models play an increasingly common role in mine water management. The aim of the paper is to present and illustrate theoretical aspects and practical strategies facilitating groundwater model set-up for mine sites by means of FEFLOW software. FEFLOW solved governing equations based on finite elements methods, which enables users to create models with very flexible meshing strategies including time-varying geometries. Unstructured and structured mesh generators allow creating very complex geological settings and with complex geometrical designs, as found for example in mine dewatering (open-cast geometry, inclined dewatering wells, inclined faults), or underground structures (pipes, tunnels, shafts etc.). In order to obtain reliable results and reduce uncertainty in provided forecast for mine sites, groundwater models often should be developed for transient condition and involve unsaturated flow and transport, fracture flow, density effects, chemical reactions, or time-varying behaviour of boundary conditions and material properties (such as conductivity or porosity). FEFLOW enables groundwater modeller set-up these all physical processes and via plug-ins extended functionality by integrated FEFLOW models with other models: geochemical (PHREEQC), watershed (MIKE 11, Hydro River) or develop user own plug-ins. Considering the above, FEFLOW seems to be appropriate software for accurate and reliable models developmentfor mine sites, and an interesting alternative for more widely used MODFLOW models in Poland.

17

Static analysis of rear suspension beam loading in a polish combine harvester

Bartoszuk M., Winiarski P., Nosol A.

Journal of Research and Applications in Agricultural Engineering

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2017

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Vol. 62, nr 2

7--11

EN

This article shows the static analysis of rear suspension beam loading in a combine harvester manufactured by New Holland Bizon Sp. z o.o. The model of the examined machine with thresher rotor (Z110 model) was being manufactured until 2001, and further modifications of combine harvesters with the mentioned threshing system are being made so far [1]. The research conducted with the use of programs: Inventor 2017 for generating the digital model and Nastran In-CAD 2017 for simulation calculations. The aim of this article is to analyze and evaluate the accuracy of the combine harvester Bizon Z110 construction. The findings of the study suggest a possibility of stress accumulation in welded joints of construction. In result, solutions to the described problems were provided.

PL

Niniejszy artykuł przedstawia analizę statyczną belki nośnej wózka tylnego kombajnu zbożowego produkowanego przez New Holland Bizon Sp. z o.o. Model analizowanej maszyny o omłocie rotorowym (wersji Z110) był produkowany do 2001 roku, a kolejne modyfikacje kombajnów zbożowych o wspomnianym systemie omłotowym produkowane są do chwili obecnej [1]. Do badań wykorzystano: pakiet Inventor 2017 dla wygenerowania modelu numerycznego, natomiast do obliczeń symulacyjnych - Nastran in Cad 2017. Celem artykułu jest analiza i ocena prawidłowości konstrukcji ramy kombajnu zbożowego Bizon Z110. Uzyskane wyniki wskazują na możliwość kumulowania się naprężeń w węzłach spawanych ramy. W konsekwencji zaproponowano możliwość rozwiązania opisywanych problemów.

18

L∞ -error estimates of finite element methods with Euler time discretization scheme for an evolutionary HJB equations with nonlinear source terms

Boulaaras S., Bencheikh Le Hocine M. A., Haiour M.

Journal of Applied Mathematics and Computational Mechanics

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2017

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Vol. 16, nr 1

19--31

EN

The main purpose of this paper is to analyze the convergence of the proposed algorithm of the finite element methods coupled with a Euler discretization scheme. Also, an optimal error estimate with an asymptotic behavior in uniform norm are given for an evolutionary nonlinear Hamilton Jacobi Bellman (HJB) equation with respect to the Dirichlet boundary conditions.

19

A remark on material parameter identification using finite elements based on constitutive models of evolutionary-type

Hartmann S.

Computer Assisted Methods in Engineering and Science

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2017

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Vol. 24, no. 2

113--126

EN

In this paper, we show that sensitivity analysis in connection with material parameter identification problems – using implicit finite elements of quasi-static problems on the basis of evolutionary-type constitutive equations – is related to simultaneous sensitivity equations and internal numerical differentiation. Thus, this study mainly focuses on investigating how these approaches are connected to the solution procedures based on finite elements. In addition, we discuss how to consider reaction forces in the sensitivity analysis, as this aspect is often neglected despite the fact that experimental results often involve force data.

20

Numerical results quality in dependence on Abaqus plane stress elements type in big displacements compression test

Kawecki B., Podgórski J.

Applied Computer Science

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2017

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Vol. 13, no 4

56--64

EN

The paper presents a brief description of the Abaqus Simulia plane stress quadrilateral elements (CPS4R, CPS4I, CPS4, CPS8R, CPS8). Comparison of the results quality obtained using each of them was done. There was considered two dimensional big displacements compression test for a highly orthotropic material. Simulations were performed for the compression in two perpendicular directions.