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1

An Improved Approach in the Application of an Elastic-Plastic Contact Force Model in the Modelling of Multiple Impacts

Warzecha Mariusz, Grzejda Rafał

Tribologia

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2023

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nr 1

85--97

EN

This paper presents the modelling of a simultaneous multiple collision occurring between several bodies of a kinematic chain. An algorithm is proposed that when used with an elastoplastic contact model, allows the phenomena that can occur during a multiple-body collision to be taken into account. These phenomena include the transition of the collision state from the restitution phase directly to the compression phase or successive collisions occurring along the same normal. The proposed algorithm can be used with any elastoplastic contact model. This paper presents its use with a selected model in a three-body system. Numerical calculations based on the model have been verified using the Finite Element Method (FEM). The use of the proposed improved approach reduces the post-collision velocity prediction error by 2.34% compared to the baseline description of collisions known from the literature.

PL

W artykule przedstawiono modelowanie symultanicznego zderzenia wielokrotnego zachodzącego pomiędzy kilkoma ciałami łańcucha kinematycznego. Zaproponowano algorytm, który wykorzystany z elasto-plastycznym modelem kontaktu pozwala na uwzględnienie zjawisk, które mogą wystąpić w trakcie zderzenia wielokrotnego. Do zjawisk tych zaliczyć można przejście stanu zderzenia z fazy restytucji bezpośrednio do fazy kompresji czy też kolejne zderzenia zachodzące wzdłuż tej samej normalnej. Zaproponowany algorytm może zostać wykorzystany z dowolnym, elasto-plastycznym modelem kontaktu. W artykule przedstawiono jego wykorzystanie z wybranym modelem w modelu składającym się z trzech ciał. Obliczenia numeryczne przeprowadzone na podstawie modelu zostały zweryfikowane za pomocą Metody Elementów Skończonych (MES). Zastosowanie zaproponowanego, ulepszonego podejścia pozwala na zmniejszenie błędu przewidywania prędkości po zderzeniu o 2.34% w porównaniu z opisem bazowym zderzenia znanym z literatury.

2

Non-uniqueness of fracture parameter choice in simulations of concrete cracking at mesoscale level

Kondys B., Bobinski J., Marzec I.

Archives of Mechanics

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2023

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Vol. 75, nr 3

365--396

EN

In the paper a non-uniqueness of fracture parameter choice in simulations of cracking process in plain concrete specimens at mesoscale level under monotonic static loading is analysed. The Finite Element Method is used, where cracks are defined in a discrete way using interface cohesive elements with nonlinear material law including softening. The concrete mesostructure (such as: cement matrix, air voids, aggregates, and Interfacial Transitions Zones (ITZ)) is taken into account. Two benchmarks: Montevideo splitting test (MVD) as a main test and the three-point beam bending test (TPBT) as an auxiliary problem are simulated. Results from 2D calculations are compared with experimental outcomes, especially force-crack opening curves and crack patterns are carefully studied. In the MVD test, the mesostructure of a specimen is taken from X-ray micro-computed tomography scans of real samples. The issue of the proper selection of material parameters for cohesive cracks is investigated. The ambiguity of such a process is presented and discussed. It turns out the numerical simulations can give the same outcome for different values of material parameters. The influence of the selected material parameters and the friction coefficient on results (force–crack opening curves and crack patterns) is also analysed.

3

Validation of Extension-Bending and Extension-Twisting Coupled Laminates in Elastic Element

Falkowicz Katarzyna

Advances in Science and Technology. Research Journal

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2023

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Vol. 17, no 3

309--319

EN

The article deals with the design of the stacking sequence of layers in composite plate element in order to create the desired behaviour in the postcritical range. Tested plates were made of carbon fiber reinforced polymer (CFRP) laminate with different layer arrangement. As the type of load, the axial compression was assumed. The configurations have been choosen specifically to investigate the influence of Extension-Twisting and Extension-Bending coupled designs under axial load. To analyse the influence of layer arrangement on the posbuckling behaviour the parametric study was performed. Matlab software and a script developed by the author were used to calculate the components of ABD matrix. Additionally, the experimental validation was carried out together with numerical analysis.

4

Influence of Composite Lay-Up on the Stability of Channel-Section Profiles Weakened by Cut-Outs – A Numerical Investigation

Falkowicz Katarzyna, Valvo Paolo Sebastiano

Advances in Science and Technology. Research Journal

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2023

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Vol. 17, no 1

108--115

EN

This paper presents a numerical study on the stability of composite channel-section profiles weakened by cut-outs. Profiles were made from carbon fibre-reinforced polymer (CFRP) laminates and subjected to compression load. Numerical analysis carried out in the Abaqus software allowed us to determine the value of the buckling load and the corresponding buckling form. Four different laminate lay-ups were chosen to study their effects on the buckling behaviour of the profiles. Obtained results help identify the best laminate lay-up to get the highest critical buckling load for perforated columns. The performed analysis shows that [45/-45/90/0]s and [90/-45/45/0]s composite lay-ups have the greatest impact on the buckling load. Moreover, the introduced perforation caused a change in the buckling form and a decrease in the critical load value.

5

Determination of Critical Damage Function Values of CW008A Copper and S355 Steel in Tensile and Torsion Tests

Walczuk-Gągała Patrycja, Pater Zbigniew, Wójcik Łukasz, Lis Konrad

Advances in Science and Technology. Research Journal

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2023

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Vol. 17, no 2

173--180

EN

The article describes the problem of material fracture in metal forming processes. It describes and compares the values of damage functions obtained in classical tensile and torsion tests of two materials, i.e. CW008A copper and S355 steel under cold forming conditions. The presented research methodology includes experimental tests and numerical simulation carried out using Simufact.Forming v.15 software. The damage values were analysed according to various criteria, including the growth and coalescence of micro cracks (Rice&Tracey, Oyane, Argon), the initiation and development of ductile cracking in forming processes (Freudenthal, Cockroft-Latham, Brozzo, Oh) and using extended phenomenological models based on the history of stress triaxiality (Ayada) or the mean and equivalent stress (Zhan). The conducted tests showed that the values of the damage function depend on: the calibration test, the material grade and the geometry of the specimen.

6

Insight into Damping Sources in Turbines

Moneta Grzegorz

Fatigue of Aircraft Structures

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2022

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Iss. 14

69--82

EN

Blade vibrations in aircraft engines are a significant challenge that must be overcome during the design and development of modern turbine engines. Vibrations lead to cyclic displacements and result in alternating stress and strain in undesired environments (high temperatures, erosion, corrosion of the surface, etc.). Under resonance conditions, stress amplitudes can increase and exceed their safety limits, and in extreme cases, can lead to engine failure. One method to reduce resonance vibrations is to increase damping in the turbine assembly. This paper presents and describes vibration damping sources in the turbine, including aerodynamic, material, and friction damping. Additionally, typical damping values for each damping component are presented and compared.

7

Application of Smoothed Particle Hydrodynamics Method in Metal Processing: An Overview

Nguyen Trang Thi Thu, Hojny Marcin

Archives of Foundry Engineering

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2022

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Vol. 22, iss. 3

67--80

EN

Smoothed Particle Hydrodynamics (SPH) is a Lagrangian formula-based non-grid computational method for simulating fluid flows, solid deformation, and fluid structured systems. SPH is a method widely applied in many fields of science and engineering, especially in the field of materials science. It solves complex physical deformation and flow problems. This paper provides a basic overview of the application of the SPH method in metal processing. This is a very useful simulation method for reconstructing flow patterns, solidification, and predicting defects, limitations, or material destruction that occur during deformation. The main purpose of this review article is to give readers better understanding of the SPH method and show its strengths and weaknesses. Studying and promoting the advantages and overcoming the shortcomings of the SPH method will help making great strides in simulation modeling techniques. It can be effectively applied in training as well as for industrial purposes.

8

Meshless local Petrov-Galerkin method for rotatingRayleigh beam using Chebyshev and Legendre polynomials

Panchore Vijay

Archive of Mechanical Engineering

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2022

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LXIX, nr 2

301-–318

EN

The numerical solutions are obtained for rotating beams; the inclusion of centrifugal force term makes it difficult to get the analytical solutions. In this paper, we solve the free vibration problem of rotating Rayleigh beam using Chebyshev and Legendre polynomials where weak form of meshless local Petrov-Galerkin method is used. The equations which are derived for rotating beams result in stiffness matrices and the mass matrix. The orthogonal polynomials are used and results obtained with Chebyshev polynomials and Legendre polynomials are exactly the same. The results are compared with the literature and the conventional finite element method where only first seven terms of both the polynomials are considered. The first five natural frequencies and respective mode shapes are calculated. The results are accurate when compared to literature.

9

Analysis of the effect of projectile impact angle on the puncture of a steel plate using the finite element method in abaqus software

Rosłaniec Kuba

Applied Computer Science

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2022

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Vol. 18, no 1

56--69

EN

This paper deals with the punctureability of a steel plate by a projectile at different angles of attack. The effect of the projectile angle on the force required to penetrate a plate made of A36 steel is presented using Finite Element Method calculation software. Using Abaqus software, a dynamic model of a projectile striking a plate was modelled and the force required to penetrate a 5 mm thick steel plate was presented. The intro-duction gives an overview of the genesis of the topic and a brief historical background. The chapter on numerical analysis presents the numerical model used and how the simulation was modelled. In the conclusions, a summary of the results was formulated and conclusions were drawn regarding the observations and insights of the analysis. The force required to penetrate the plate was observed to increase with increasing projectile angle of attack and it was found that, as the angle of the plate increased, the force required to penetrate increased.

10

Numerical analysis for the beam with composite dowels connector

Kasza Przemysław, Lacki Piotr, Derlatka Anna

Zeszyty Naukowe Politechniki Częstochowskiej. Budownictwo

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2021

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Z. 27 (177)

92-100

PL

Celem pracy była analiza numeryczna modelu belki zespolonej z nowatorskim kształtem łącznikiem w postaci wyciętego środnika. Rozpatrywany model może mieć zastosowanie jako zespolony podciąg stropowy lub dźwigar mostowy. Badany rodzaj łącznika był odpowiednio wyprofilowaną częścią środnika kształtownika stalowego. Pierwsza część pracy polegała na analitycznym zaprojektowaniu belki zespolonej. Dobrano przekrój gorącowalcowany z połowy kształtownika gorącowalcowanego HEB. Druga część pracy polegała na zamodelowaniu belki zespolonej. Geometrię belki, obciążenie oraz warunki brzegowe zastosowano takie, jak w części pierwszej pracy. Analizę numeryczną przeprowadzono za pomocą programu ADINA System opartego na metodzie elementów skończonych. Profil stalowy HEB i płytę żelbetową zamodelowano za pomocą elementów typu 3D Solid, natomiast pręty zbrojeniowe zamodelowano za pomocą elementów typu truss. Dokonano oceny naprężeń i odkształceń w elemencie stalowym i betonowym, rozkładu sił w prętach zbrojenia oraz zarysowania betonu.

EN

The focus of the study was on the numerical analysis of the model of the beam integrated with the innovative shape of connector in the form of the cut-out web. The model can be used as an integrated binding joist or bridge girder. This type of connector was a specifically shaped part of the web of the steel section. The first part of the study was focused on the analytical design of the integrated beam. A hot-rolled cross-section was chosen from the half of the hot-rolled HEB section. The second part of the study was modelling of the integrated beam. Beam geometry, load and boundary conditions were used as in the first part of the study. ADINA software, based on the finite elements method, was used for numerical analysis. The HEB steel section and the reinforced concrete slab were modelled by means of 3D Solid elements, whereas the rein-for cement bars were modelled using truss type elements. The stresses and strain in the steel and concrete elements, distribution of forces in reinforcement bars and concrete cracking were evaluated.

11

Free vibrations of Kirchhoff plates considering plate variable thickness and interaction with water including water boundaries

Lenartowicz Agnieszka, Guminiak Michał, Przychodzki Maciej

Vibrations in Physical Systems

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2021

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Vol. 32, nr 2

art. no. 2021208

EN

The natural vibrations of thin (Kirchhoff-Love) plates with constant and variable thickness and interaction with water are considered in the paper. The influence of the water free surface on natural frequencies of the coupled water-plate system is analysed too. The Finite Element Method (FEM) and the Finite Difference Method (FDM) are used to describe structural deformation and the Boundary Element Method (BEM) is applied to describe the dynamic interaction of water on a plate surface. The plate inertia forces are expressed by diagonal or consistent mass matrix. The water inertia forces are described by fully-populated mass matrix which is obtained directly from the theory of double layer potential.

12

Modelowanie interakcji pojazd-most w warunkach deformacji niwelety drogi

Kużawa Mieszko, Mróz Aleksander, Kliński Maksymilian, Bień Jan, Rabiega Józef

Przegląd Komunikacyjny

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2021

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R. 76, nr 6/7

2--7

PL

W artykule przedstawiono metodę i wyniki symulacji numerycznych wzajemnych oddziaływań dynamicznych pomiędzy pojazdami a konstrukcją mostu, która ma uszkodzenia w postaci nadmiernych trwałych ugięć przęseł. Analizy symulacyjne przeprowadzono na przykładzie rzeczywistego autostradowego obiektu mostowego, na którym stwierdzono występowanie trwałych deformacji niwelety jezdni. Jako obciążenie ruchome zamodelowano typowy 5-osiowy samochód ciężarowy o całkowitej masie 40 t. W trakcie analiz główną uwagę zwrócono na wartości pionowych przemieszczeń i przyspieszeń drgań przęseł mostu generowanych przez pojazdy ciężarowe w funkcji intensywności trwałych ugięć konstrukcji przęseł oraz prędkości pojazdu.

EN

The paper presents a method and results of numerical simulations of dynamic interactions between vehicles and the bridge structure, which has defects in the form of excessive permanent deflections of their spans. The simulation analyzes were carried out on the example of a real motorway bridge, on which the presence of such defects was found. A typical 5-axle truck with a total weight of 40 tons was modeled as a moving load. During the analyzes, the main attention was paid to the values of vertical displacements and accelerations of vibrations of the bridge spans generated by heavy vehicles as a function of the intensity of permanent deflections of the structure and the vehicles speed.

13

Comparison of the efficiency of the WPT system using circular or square planar coils

Stankiewicz Jacek Maciej

Przegląd Elektrotechniczny

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2021

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R. 97, nr 10

38--43

EN

The article presents results for numerical analysis of Wireless Power Transfer (WPT) system consisting of transmitting and receiving plane coils. Two types of coils (circular and square) were included in the analysis. The influence of the type of coils, the number of turns and the distance between the coils on the efficiency of the WPT system was compared. The analysis covered a wide range of frequencies from 100 kHz to 1000 kHz. The Finite Element Method (FEM) with the using antiperiodic boundary conditions for the analysis was used. In the low frequency range (within the analysed range) the higher efficiency is for the WPT system composed of square coils. On the other hand, at higher frequency values, higher efficiency values were obtained for the WPT model containing circular coils. Proposed WPT system could be used to charge electric devices as the wireless power transfer system. The results indicate at which system parameters wireless energy transfer is possible.

PL

W artykule przedstawiono wyniki analizy numerycznej systemu Wireless Power Transfer (WPT) składającego się z cewek płaskich nadawczo-odbiorczych. W analizie uwzględniono dwa rodzaje cewek (okrągła i kwadratowa). Porównano wpływ rodzaju cewek, liczby zwojów oraz odległości między cewkami na sprawność układu WPT. Analiza obejmowała szeroki zakres częstotliwości od 100 kHz do 1000 kHz. Do analizy wykorzystano Metodę Elementów Skończonych (MES) z wykorzystaniem antyperiodycznych warunków brzegowych. W zakresie niskich częstotliwości (w analizowanym zakresie) wyższa sprawność występuje dla układu WPT złożonego z cewek kwadratowych. Natomiast przy wyższych wartościach częstotliwości wyższe wartości sprawności uzyskano dla modelu WPT zawierającego cewki okrągłe. Proponowany system WPT mógłby służyć do ładowania urządzeń elektrycznych jako bezprzewodowy system przesyłania energii. Wyniki wskazują, przy jakich parametrach układu możliwy jest bezprzewodowy transfer energii.

14

Consideration of the uncertainty in the dimensioning of a gearbox of a wind turbine

Trabelsi Hassen, Guizani Amir, Barkallah Maher, Hammadi Moncef, Hadrich Ayman

Journal of Theoretical and Applied Mechanics

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2021

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Vol. 59 nr 1

67--79

EN

The paper deals with the design approach of a subdefinite mechatronic system and focuses on the sizing stage of a gearbox of a wind turbine based on the interval computation method. Indeed, gearbox design variables are expressed by intervals to take into account the uncertainty in the estimation of these parameters. The application of the interval computation method allows minimizing the number of simulations and enables obtaining a set of solutions instead of a single one. The dynamic behavior of the gearbox is obtained using the finite element method. The challenge here is to get convergent results with intervals that reflect the efficiency of the applied method. Thus, several mathematical formulations have been tested in static study and evaluated in the case of a truss. Then the interval computation method was used to simulate the behavior of the wind turbine gearbox.

15

Investigation of the influence of liquid phase motion on the solidification process in the three-dimensional region

Węgrzyn-Skrzypczak Ewa

Journal of Applied Mathematics and Computational Mechanics

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2021

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Vol. 20, nr 1

103--111

EN

In this paper, the numerical model of solidification process with the motion of the liquid phase is presented. The mathematical description of the considered problem is based on the heat conduction equation with convective term and the Navier-Stokes equations with continuity equation. The numerical model uses the Finite Element Method (FEM). The simulations of the solidification process with or without the fluid motion effect are presented and discussed.

16

Study on the temperature and strain fields in gas foil bearings – measurement method and numerical simulations

Zdziebko Paweł, Martowicz Adam

Eksploatacja i Niezawodność

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2021

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Vol. 23, no. 3

540--547

EN

Gas foil bearings belong to the group of slide bearings and are used in devices in which operation at high rotational speeds of the shafts are of key importance, e.g., in gas turbines. The air film developed on the surface of the bearing’s top foil allows this structural component to be separated from the shaft. This ensures a non-contact operation of the bearing. In the case of the mentioned type of bearings, their resultant operational properties are influenced by both thermal and mechanical phenomena. The current work presents a model of a gas foil bearing developed making use of the Finite Element Method. The model takes into account thermomechanical couplings which are necessary for the correct simulation of the operation of physical components of the modeled system. The paper reports the results of numerical analyzes conducted for the elaborated model as well as the relevant conclusions concerning thermomechanical couplings present in gas foil bearings. The method for the experimental identification of the temperature and strain fields in the bearing’s top foil proposed to validate the numerical model is also presented.

17

Evaluation of the influence of friction in a multi-leaf spring on the working conditions of a truck driver

Hryciów Zdzisław, Krasoń Wiesław, Wysocki Józef

Eksploatacja i Niezawodność

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2021

|

Vol. 23, no. 3

422--429

EN

This article presents a simulation study of the suspension system in a vehicle that weighs approximately 12 tons (class N2). The authors have tested the influence of experimentally determined values of friction coefficients on the energy dissipated in the multi-leaf spring. The study was carried out using finite element analysis with LS-DYNA software. A nonlinear vibration model of the complete spring was developed, including the variable friction forces between the leafs. The model takes into account the sprung and unsprung mass of the chassis. Numerical tests were carried out using three different coefficients of friction (determined experimentally) for a selected speed of the car. Random realizations of the road micro-profile (type A, B, C) recommended by ISO 8608 were used. The results of the tests were presented in the form of acceleration curves in the vertical direction, comparative plots of daily vibration exposure A(8) and vibration transmission coefficient (T), and the distributions of RMS acceleration in frequency of one-third octave bands. This data was used to assess the quality of the vibration isolation system between the front suspension of the vehicle and the driver’s seat.

18

2D and 3D preliminary numerical analysis of a masonry arch - case study

Jurczak Marlena Anna

Budownictwo o Zoptymalizowanym Potencjale Energetycznym

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2021

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Vol. 10 Nr 2

127--136

EN

Masonry arches are regularly used in construction. The main purpose of this work was to perform numerical calculations using the Finite Element Method to estimate the load capacity of the designed masonry arch and to identify optimal locations for sensors on a real structure to aid advanced structural analysis. The model was implemented in two computer programs - Autodesk Robot and DIANA, and the results were compared. The arch was analysed statically and dynamically in the elastic range. A preliminary 2D static analysis was performed in Autodesk Robot, while in DIANA both flat and spatial models were analysed using both static and dynamic analysis. Numerical estimation of the load capacity of the masonry structure gave the opportunity to show the basic failure mechanisms together with the character of the stress distribution as well as the eigenfrequencies and eigenmodes. Satisfactory results were obtained, after a review of the literature.

19

Modeling of the Elastic Plates of Non-Base Configurations for the Cams of Automatic Half-Hose Machines

Berezin Leonid, Savchenko Kyrylo, Rubanka Mykola, Polishchuk Oleh, Oliinyk Olena, Rubanka Alla

Advances in Science and Technology. Research Journal

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2021

|

Vol. 15, no 1

92--98

EN

The purpose of the work was analytical research and computer modeling of the influence of shape and size of console beams of elastic plates in non-base configurations for the cam of the automatic half-hose machine under the conditions of flexibility, strength, and minimization of sizes. The scientific novelty of the work lies in the further development of the theory and methodology of designing the elements of knitting systems of the automatic half-hose machines based on regimes of loading, limitations in strength and dimensions, as well as requirements of the technological process. In order to increase the flexibility of the elastic plate, the symmetrical introduction of two console beams of trapezoidal shape was proposed. The influence exerted by the coefficient of the shape of console beams and their lengths on the magnitudes of deflections and stresses was analyzed, which allows making grounded and flexible decisions regarding the dimensions of the root and the end sections of the beams at the preliminary stage of design. The mathematical support was presented mainly in an explicit form, which simplified the analysis of the influence of controlled dimensions of the elastic plates on their flexibility and strength, as well as contributes to the comprehensive approach to the development of cams of different constructions with elastic plates and allows improving the quality and efficiency of design solutions of cams. The beam bending theory and the finite element method based on Code_Aster shared software were used. The model of the plate was represented by an ordered grid of finite nodal elements of the same size, without the use of elongated and flat elements. According to the results of simulation experiments, the distributions of deformations and stresses on the surface of the elastic plate of the cam were obtained, depending on its shape and size, which confirmed the validity of calculated recommendations.

20

Free vibrations of iso- and orthotropic plates considering plate variable thickness and interaction with water

Lenartowicz Agnieszka, Guminiak Michał

Vibrations in Physical Systems

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2020

|

Vol. 31, nr 2

art. no. 2020216

EN

The natural vibrations of thin (Kirchhoff-Love) plates with constant and variable thickness are considered in the paper. Isotropic and orthotropic rectangular plates with different boundary conditions are analysed. The Finite Element Method and the Finite Difference Method are used to describe structural deformation. The elements of stiffness matrix are derived numerically using author’s approaches of localization of integration points. The plate inertia forces are expressed by diagonal, lumped mass matrix or consistent mass matrix. The presence of the external medium, which can be a fluid, is described by the fluid velocity potential of double layer and the fundamental solution of Laplace equation which leads to the fully-populated mass matrix. The influence of external additional liquid mass on natural frequencies of plate is analysed, too.