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    Wyświetlanie 1-18 z 18
    Tytuł:
    Finite element modeling for electric field and voltage distribution along the cap and pin insulators under pollution
    Autorzy:
    Ghermoul, Oussama
    Benguesmia, Hani
    Benyettou, Loutfi
    Powiązania:
    https://bibliotekanauki.pl/articles/2203634.pdf
    Data publikacji:
    2023
    Wydawca:
    Polska Akademia Nauk. Polskie Towarzystwo Diagnostyki Technicznej PAN
    Tematy:
    1512L
    electric field
    electrical potential
    COMSOL Multiphysics
    pollution
    pole elektryczne
    potencjał elektryczny
    zanieczyszczenie
    oprogramowanie COMSOL Multiphysics
    Opis:
    The knowledge of the behavior of both the electric potential and electric field is one of the main factors needed when designing an insulator. Using AutoCAD software a 2D cap and pin 1512L insulator model was created in the clean state and under pollution from one to five insulators separately making a chain of insulators for a total of 10 models. Later they are imported to COMSOL Multiphysics 5.6 software, simulations of the 1512L insulator were made to see the effect the pollution has and the differences that occur on the distribution with the addition of more insulators in the chain. The potential distribution starts to develop a pattern after a certain number of insulators in the chain while the pollution induces high value spikes in the field distribution. Finite-element-analysis for numerical simulation of the pollution effect in outdoor insulators: a review and a novel method.
    Źródło:
    Diagnostyka; 2023, 24, 2; art. no. 2023201
    1641-6414
    2449-5220
    Pojawia się w:
    Diagnostyka
    Dostawca treści:
    Biblioteka Nauki
    Artykuł
    Tytuł:
    1-D equivalent circuit for RF MEMS capacitive switch
    Autorzy:
    Kula, S.
    Powiązania:
    https://bibliotekanauki.pl/articles/377903.pdf
    Data publikacji:
    2014
    Wydawca:
    Politechnika Poznańska. Wydawnictwo Politechniki Poznańskiej
    Tematy:
    RF MEMS switch
    equivalent circuits for MEMS
    multiphysics modeling
    Opis:
    In this paper the equivalent circuit for an accurate model of the RF (Radio Frequency) MEMS (Micro Electro-Mechanical Systems) capacitive switch is presented. The capacitive switch consists of a thin metal membrane, which name is bridge suspended over central conductor and connected at both ends to the ground conductor of CPW (coplanar waveguide). The equivalent circuit was created based on multi-physic modelling, elements analogues, and electrical equivalences. Mechanical and electrical forces are included in the equivalent circuit as current sources. The usefulness and effectiveness of the model was verified through results comparison with the commercial APLAC software and mathematical modelling in Matlab software. The novelty of the paper is the equivalent circuit, which is useful to simulate linear and non-linear cases of the RF MEMS capacitive switch and also the novelty is an implementation of the equivalent circuit in LTSpice, which is a freeware circuits simulator.
    Źródło:
    Poznan University of Technology Academic Journals. Electrical Engineering; 2014, 80; 175-181
    1897-0737
    Pojawia się w:
    Poznan University of Technology Academic Journals. Electrical Engineering
    Dostawca treści:
    Biblioteka Nauki
    Artykuł
    Tytuł:
    Research and Modeling of Mechanical Crosstalk in Linear Arrays of Ultrasonic Transducers
    Autorzy:
    Celmer, M.
    Opieliński, K.
    Powiązania:
    https://bibliotekanauki.pl/articles/176916.pdf
    Data publikacji:
    2016
    Wydawca:
    Polska Akademia Nauk. Czytelnia Czasopism PAN
    Tematy:
    mechanical crosstalk
    ultrasonic transducer array
    FEM modeling
    COMSOL Multiphysics
    Opis:
    Linear arrays of ultrasonic transducers are commonly used as ultrasonic probes in medical diagnostics for imaging the interior of a human body in vivo. The crosstalk phenomenon occurs during the operation of transducers in which electrical voltages and mechanical vibrations are transmitted to adjacent components. As a result of such additional excitation of the transducers in the array, the directivity characteristics of the aperture used changes, and consequently there is interference with proper operation of a given array and the emergence of distortions in the obtained ultrasound image that reduce its quality. This paper studies the manner of propagation of mechanical crosstalk in the designed model of a linear array of ultrasonic transducers on the basis of unwanted signals, which appeared on elementary piezoelectric transducers when power is supplied to the selected transducer in the array. The universal model of linear array of ultrasonic transducers, which has been developed, allowed the simulation of mechanical crosstalk, taking into account the cross-coupling phenomenon in all of its structure with the use of finite elements method (FEM) implemented in COMSOL Multiphysics software. The analysis of crosstalk signals showed that they consist of aggregated pulses propagating with different speeds and frequencies. This signifies the formation of different vibration modes transmitted simultaneously via different paths. The paper is an original approach which enables to identify different vibration modes and estimate their participation in the crosstalk signal and their ways of propagation. Conclusions from the research allow predicting specific design changes which are significant due to the minimization of mechanical crosstalk in linear arrays of ultrasonic transducers.
    Źródło:
    Archives of Acoustics; 2016, 41, 3; 599-612
    0137-5075
    Pojawia się w:
    Archives of Acoustics
    Dostawca treści:
    Biblioteka Nauki
    Artykuł
    Tytuł:
    Fault detection and diagnosis of squirrel cage asynchronous motor using a new COMSOL multiphysics software 6.0.
    Autorzy:
    Djaidir, Benrabeh
    Nail, Bachir
    Rouibah, Abdelkader
    Powiązania:
    https://bibliotekanauki.pl/articles/27313810.pdf
    Data publikacji:
    2024
    Wydawca:
    Polska Akademia Nauk. Polskie Towarzystwo Diagnostyki Technicznej PAN
    Tematy:
    asynchronous motor
    comsol multiphysics
    diagnosis
    fault detection
    flux density
    Opis:
    In this paper, the diagnosis of faults in squirrel cage asynchronous motor and experimental analysis process are presented. Currently there are several simulation tools, that lets users analyze and interpret the behavior of their devices. Based on this, there is a lot of researches that is working on developing models, to detect and classify 3-phase asynchronous motor faults, significantly in the early stages. This work proposed design and experimental analysis established in Comsol Multiphysics 6.0 , which implements finite element analysis software (FEM) for detecting and diagnosing broken bar rotors of this types motors and its practical application. In this case, the post processor of the COMSOL-Multiphysics makes it possible to visualize in 2D the various magnetic and mechanical quantities. Through the curves of the magnetic flux density and analysis distribution of the field with magnetic induction lines, we can draw some conclusions, where we proposed an strategy, for detecting and diagnosing faults consistent with the structure of the software.
    Źródło:
    Diagnostyka; 2024, 25, 1; art. no. 2024102
    1641-6414
    2449-5220
    Pojawia się w:
    Diagnostyka
    Dostawca treści:
    Biblioteka Nauki
    Artykuł
    Tytuł:
    Simulation of the Moulding Process of Bentonite-Bonded Green Sand
    Autorzy:
    Abdulamer, D.
    Kaduaw, A.
    Powiązania:
    https://bibliotekanauki.pl/articles/1837740.pdf
    Data publikacji:
    2021
    Wydawca:
    Polska Akademia Nauk. Czytelnia Czasopism PAN
    Tematy:
    green sand mould
    moulding processes
    COMSOL multiphysics
    time-dependent study
    Opis:
    Finite Element Method FEM via commercially available software has been used for numerical simulation of the compaction process of bentonite-bonded sand mould. The mathematical model of soil plasticity which involved Drucker-Prager model match with Mohr Coulomb model was selected. The individual parameters which required for the simulation process were determined through direct shear test based on the variation of sand compactability. The novelty of this research work is that the individual micro-mechanical parameters were adopted depend on its directly proportional to the change of sand density during the compaction process. Boundary conditions of the applied load, roller and fixed constraint were specified. An extremely coarse mesh was used and the solution by time-dependent study was done for investigation of material-dependent behaviour of green sand during the compaction process. The research implemented also simulation of the desired points in sand mould to predict behaviour of moulding process, and prevent failure of the sand mould. Distance dependent displacement and distance-dependent pressure have been determined to investigate the effective moulding parameters without spent further energy and cost for obtaining green sand mould. The obtained numerical results of the sand displacement show good agreement with the practical results.
    Źródło:
    Archives of Foundry Engineering; 2021, 21, 1; 67-73
    1897-3310
    2299-2944
    Pojawia się w:
    Archives of Foundry Engineering
    Dostawca treści:
    Biblioteka Nauki
    Artykuł
    Tytuł:
    Simulation of the Moulding Process of Bentonite-Bonded Green Sand
    Autorzy:
    Abdulamer, D.
    Kaduaw, A.
    Powiązania:
    https://bibliotekanauki.pl/articles/1837861.pdf
    Data publikacji:
    2021
    Wydawca:
    Polska Akademia Nauk. Czytelnia Czasopism PAN
    Tematy:
    green sand mould
    moulding processes
    COMSOL multiphysics
    time-dependent study
    Opis:
    Finite Element Method FEM via commercially available software has been used for numerical simulation of the compaction process of bentonite-bonded sand mould. The mathematical model of soil plasticity which involved Drucker-Prager model match with Mohr Coulomb model was selected. The individual parameters which required for the simulation process were determined through direct shear test based on the variation of sand compactability. The novelty of this research work is that the individual micro-mechanical parameters were adopted depend on its directly proportional to the change of sand density during the compaction process. Boundary conditions of the applied load, roller and fixed constraint were specified. An extremely coarse mesh was used and the solution by time-dependent study was done for investigation of material-dependent behaviour of green sand during the compaction process. The research implemented also simulation of the desired points in sand mould to predict behaviour of moulding process, and prevent failure of the sand mould. Distance dependent displacement and distance-dependent pressure have been determined to investigate the effective moulding parameters without spent further energy and cost for obtaining green sand mould. The obtained numerical results of the sand displacement show good agreement with the practical results.
    Źródło:
    Archives of Foundry Engineering; 2021, 21, 1; 67-73
    1897-3310
    2299-2944
    Pojawia się w:
    Archives of Foundry Engineering
    Dostawca treści:
    Biblioteka Nauki
    Artykuł
    Tytuł:
    Biogeography-inspired multiobjective optimization for helping MEMS synthesis
    Autorzy:
    Di Barba, P.
    Mognaschi, M. E.
    Venini, P.
    Wiak, S.
    Powiązania:
    https://bibliotekanauki.pl/articles/140410.pdf
    Data publikacji:
    2017
    Wydawca:
    Polska Akademia Nauk. Czytelnia Czasopism PAN
    Tematy:
    biogeography-inspired optimisation
    finite-element method
    MEMS
    multiphysics
    analysis
    Pareto optimality
    Opis:
    The aim of the paper is to assess the applicability of a multi-objective biogeography- based optimisation algorithm in MEMS synthesis. In order to test the performances of the proposed method in this research field, the optimal shape design of an electrostatic micromotor, and two different electro-thermo-elastic microactuators are considered as the case studies.
    Źródło:
    Archives of Electrical Engineering; 2017, 66, 3; 607-623
    1427-4221
    2300-2506
    Pojawia się w:
    Archives of Electrical Engineering
    Dostawca treści:
    Biblioteka Nauki
    Artykuł
    Tytuł:
    Topology optimization - broadening the areas of application
    Autorzy:
    Bendsoe, M. P.
    Lund, E.
    Olhoff, N.
    Sigmund, O.
    Powiązania:
    https://bibliotekanauki.pl/articles/970157.pdf
    Data publikacji:
    2005
    Wydawca:
    Polska Akademia Nauk. Instytut Badań Systemowych PAN
    Tematy:
    optymalizacja topologiczna
    laminat
    płyn
    topology optimization
    laminates
    pressure loads
    multiphysics
    fluids
    Opis:
    This paper deals with recent, developments of topology optimization techniques for application in some new types of design problems. The emphasis is on recent work of the Danish research groups at Aalborg University and at the Technical University of Denmark and focus is on the central role that the choice of objective functions and design parameterization plays for a successful extension of the material distribution approach to new design settings and to new types of physics models. The applications that will be outlined encompass design of laminated composite structures, design for pressure loads, design in fluids, design in acoustics, and design in photonics. A short outline of other design optimization activities is also given.
    Źródło:
    Control and Cybernetics; 2005, 34, 1; 7-35
    0324-8569
    Pojawia się w:
    Control and Cybernetics
    Dostawca treści:
    Biblioteka Nauki
    Artykuł
    Tytuł:
    Multiobjective shape optimization of selected coupled problems by means of evolutionary algorithms
    Autorzy:
    Długosz, A.
    Burczyński, T.
    Powiązania:
    https://bibliotekanauki.pl/articles/202348.pdf
    Data publikacji:
    2012
    Wydawca:
    Polska Akademia Nauk. Czytelnia Czasopism PAN
    Tematy:
    multiobjective optimization
    evolutionary algorithms
    multiphysics
    coupled field problems
    finite element method
    Opis:
    In present paper an improved multi-objective evolutionary algorithm is used for Pareto optimization of selected coupled problems. Coupling of mechanical, electrical and thermal fields is considered. Boundary-value problems of the thermo-elasticity, piezoelectricity and electro-thermo-elasticity are solved by means of finite element method (FEM). Ansys Multiphysics and MSC.Mentat/Marc software are used to solve considered coupled problems. Suitable interfaces between optimization tool and the FEM software are created. Different types of functionals are formulated on the basis of results obtained from the coupled field analysis. Functionals depending on the area or volume of the structure are also proposed. Parametric curves NURBS are used to model some optimized structures. Numerical examples for exemplary three-objective optimization are presented in the paper.
    Źródło:
    Bulletin of the Polish Academy of Sciences. Technical Sciences; 2012, 60, 2; 215-222
    0239-7528
    Pojawia się w:
    Bulletin of the Polish Academy of Sciences. Technical Sciences
    Dostawca treści:
    Biblioteka Nauki
    Artykuł
    Tytuł:
    Finite element method based simulation of electrical breakage of iron-phosphate ore
    Autorzy:
    Razavian, S. M.
    Rezai, B.
    Irannajad, M.
    Powiązania:
    https://bibliotekanauki.pl/articles/110295.pdf
    Data publikacji:
    2015
    Wydawca:
    Politechnika Wrocławska. Oficyna Wydawnicza Politechniki Wrocławskiej
    Tematy:
    finite element method
    numerical simulation
    electrical breakage
    iron-phosphate ore
    COMSOL Multiphysics
    Opis:
    In this study, the effect of minerals composition, particle size and shape as well as electrodes distance from iron-phosphate ore samples, was investigated by using a commercial software. Comparison between high voltage pulses and conventional crushing showed that minerals of interest in the electrical comminution product are better liberated than in the conventional comminution. In order to elucidate and confirm the experimental results, numerical simulation of electrical field distributions/intensity were performed. The software uses the finite element method, a numerical technique for calculating approximate solutions of partial differential equations with known boundary conditions. Magnetite, apatite and quartz were the basic minerals of iron-phosphate ore components, and the main material property used in the simulations was electrical permittivity. The results showed that the induced electrical field was strongly dependent on the electrical properties of minerals, the feed particle size and the location of the magnetite mineral (due to higher permittivity) in the ore. The angle of particle contact surface with high voltage electrode was an important factor in the intensity of electrical field. Smaller contact angle resulted in higher intensity of the electrical field. Electrical discharge within the material was converted to electrohydraulic discharge within the surrounding water environment by increasing the distance between the high voltage electrode and the material contact surface.
    Źródło:
    Physicochemical Problems of Mineral Processing; 2015, 51, 1; 137-150
    1643-1049
    2084-4735
    Pojawia się w:
    Physicochemical Problems of Mineral Processing
    Dostawca treści:
    Biblioteka Nauki
    Artykuł
    Tytuł:
    Numerical model of the axial magnetic bearing with six cylindrical poles
    Autorzy:
    Sikora, Bartłomiej Marian
    Pilat, Adam Krzysztof
    Powiązania:
    https://bibliotekanauki.pl/articles/141281.pdf
    Data publikacji:
    2019
    Wydawca:
    Polska Akademia Nauk. Czytelnia Czasopism PAN
    Tematy:
    Active Magnetic Bearing
    Axial Magnetic Bearing
    Finite Element Method
    numerical model
    COMSOL Multiphysics
    Opis:
    The paper presents a numerical model of the novel design of the axial magnetic bearing with six cylindrical poles. The motivation behind this idea was to eliminate vibra- tions in rotating machinery due to the axial load. Common conception of such a bearing provides a single component of the electromagnetic force, which is not enough to reduce transverse and lateral vibrations of the armature. The proposed design allows for avoiding wobbling of the disc with the use of a few axial force components that are able to actively compensate the axial load and stabilise the disc in a balanced position. Before a real device is manufactured, a virtual prototype should be prepared. The accurate numerical model will provide essential knowledge about the performance of the axial magnetic bearing.
    Źródło:
    Archives of Electrical Engineering; 2019, 68, 1; 195-208
    1427-4221
    2300-2506
    Pojawia się w:
    Archives of Electrical Engineering
    Dostawca treści:
    Biblioteka Nauki
    Artykuł
    Tytuł:
    Simulating In-Situ Leaching Process Using COMSOL Multiphysics
    Autorzy:
    Mukhanov, B. K.
    Omirbekova, Z. Z.
    Usenov, A. K.
    Wójcik, W.
    Powiązania:
    https://bibliotekanauki.pl/articles/227314.pdf
    Data publikacji:
    2014
    Wydawca:
    Polska Akademia Nauk. Czytelnia Czasopism PAN
    Tematy:
    in situ leaching
    uranium
    modeling
    partial differential equations
    Darcy's law filtration
    multiphysics
    diffusion
    Opis:
    The paper deals with simulation of in-situ uranium leaching technological process, collecting data for forecasting and leaching process control. It provides numerical simulation of uranium in-situ leaching (ISL) using Comsol Multiphysics software package a pplication. Previous studies evaluated main hydrodynamic characteristics of wells and reservoirs, such as the coefficient of resistance and the saturation recovery; while this paper is concerned with determining the changes in process variables in the wells during operation.
    Źródło:
    International Journal of Electronics and Telecommunications; 2014, 60, 3; 213-217
    2300-1933
    Pojawia się w:
    International Journal of Electronics and Telecommunications
    Dostawca treści:
    Biblioteka Nauki
    Artykuł
    Tytuł:
    Effective Thermal Characteristics Synthesis Microlevel Models in the Problems of Composite Materials Optimal Design
    Autorzy:
    Jaworski, N.
    Powiązania:
    https://bibliotekanauki.pl/articles/410799.pdf
    Data publikacji:
    2015
    Wydawca:
    Polska Akademia Nauk. Oddział w Lublinie PAN
    Tematy:
    composite materials
    optimal design
    microlevel models
    finite element method
    coupled problems
    multiphysics problems
    Opis:
    The composite materials optimal design problem which taking into account the thermal characteristics is the part of an actual structural design task. A wide range of variety of such material structures and the complexity of modeling some physical phenomena (such as the phenomenon of those structures effective characteristics percolation threshold appearing) requires a high level of detail in physico-mathematical models. Here, in this paper, were analyzed the role and place of physico-mathematical microlevel models in problems of composite materials optimal design. The methods of such materials representative volume elements construction within the model calculations, which are the key step in the modeling of complex structures variety, also were analyzed. Basing on the usage of finite element method for modeling of stationary heat conduction and elasticity linear problems was proposed the combined formalization of coupled thermoelasticity problems simulation method in complex structured composite materials, which is especially useful when used in engineering applications which provide a high level of abstraction. Basing on the analogy method and theory of similarity were developed the complex structured composite materials microlevel models, which allow one to synthesize and then re-use in the problems of composite materials optimal design, such effective thermal characteristics as thermal conduction coefficient, Young's modulus, Poisson's ratio and temperature coefficient of linear expansion. This gives the ability to avoid of classical complex mathematical homogenization processes or real experiments. The method and models were successfully implemented by using of highperformance parallel and distributed computing technologies in heterogeneous computing environments, as evidenced by the simulation results.
    Źródło:
    ECONTECHMOD : An International Quarterly Journal on Economics of Technology and Modelling Processes; 2015, 4, 2; 3-12
    2084-5715
    Pojawia się w:
    ECONTECHMOD : An International Quarterly Journal on Economics of Technology and Modelling Processes
    Dostawca treści:
    Biblioteka Nauki
    Artykuł
    Tytuł:
    Układ pomiarowy do badań charakterystyk chłodzenia radiatorów z wykorzystaniem pomiarów termowizyjnych
    The measurement system for research on characteristic of cooling of radiators using infrared thermography
    Autorzy:
    Klecha, D.
    Minkina, W.
    Powiązania:
    https://bibliotekanauki.pl/articles/267843.pdf
    Data publikacji:
    2017
    Wydawca:
    Politechnika Gdańska. Wydział Elektrotechniki i Automatyki
    Tematy:
    termografia
    termowizja
    radiatory
    konwekcja naturalna
    badania modelowe
    COMSOL Multiphysics®
    thermography
    thermovision
    radiators
    natural convection
    calculations
    Opis:
    W artykule przedstawiono metodę pozwalającą na porównanie jakości chłodzenia wybranych typów radiatorów w warunkach konwekcji swobodnej z wykorzystaniem pomiarów termowizyjnych oraz autorskiego stanowiska badawczego. W tym celu zbudowano układ pomiarowy, który może być użyty do generowania identycznych temperatur pod czterema polami grzewczymi w tym samym czasie i w tych samych warunkach wymiany ciepła. Na obszarze pól grzewczych umieszczono badane radiatory. Odczyty wartości temperatury z analogowych czujników temperatury i termogramów zostały użyte do porównania, który radiator ma najniższa temperaturę na początku i na końcu pomiarów. Wyniki badań eksperymentalnych porównano z wynikami badań modelowych z wykorzystaniem środowiska programistycznego COMSOL Multiphysics®. Pozycje literaturowe w małym stopniu opisują podobną problematykę. Na podstawie wyników uzyskanych z przeprowadzonych pomiarów i badań modelowych, sformułowano wnioski dotyczące jakości chłodzenia wybranych typów radiatorów.
    The aim of t his paper is to discuss method to compare cooling parameter in selected radiators. In this purpose measurement system was created which can be used to generate identical temperature under four radiators in the same time and conditions. Readings from analog sensors and thermograms were used to compare which radiator has the lowest temperature at the beginning and at the end of the measurement. Paper describes method to compare radiators using measurements from sensors and thermograms which is supplement to the theoretical calculations. Literature positions discuss this method slightly. Method is given capabilities to analyse whole process of cooling and deduce additional conclusions. Differences between temperatures of the radiators are noticeable and can be used to select the most performance radiator. The model research was compared with calculations form COMSOL Multiphysics®. The coolest radiator was different than this from experiment. This is the initial research. Next stage of the work will be carried out extensive research with the other radiators which will contain different shapes, weights and surface areas.
    Źródło:
    Zeszyty Naukowe Wydziału Elektrotechniki i Automatyki Politechniki Gdańskiej; 2017, 54; 117-121
    1425-5766
    2353-1290
    Pojawia się w:
    Zeszyty Naukowe Wydziału Elektrotechniki i Automatyki Politechniki Gdańskiej
    Dostawca treści:
    Biblioteka Nauki
    Artykuł
    Tytuł:
    A proper borehole pattern design for coal seam methane drainage in Tabas coal mine using Comsol Multiphysics
    Autorzy:
    Bagherzadeh, Ali
    Najafi, Mehd
    Marji, Mohammad Fatehi
    Noroozi, Mehdi
    Powiązania:
    https://bibliotekanauki.pl/articles/2201375.pdf
    Data publikacji:
    2022
    Wydawca:
    Główny Instytut Górnictwa
    Tematy:
    numerical modeling
    borehole patterns
    COMSOL Multiphysics
    CFD simulation
    coal gas drainage
    modelowanie numeryczne
    schematy otworów wiertniczych
    symulacja CFD
    odmetanowanie
    Opis:
    Optimizing the operational parameters of the borehole pattern in the coal seam includes the maximum amount of gas to be drained with the least amount of drilling, investment, and drainage time. The main purpose of this research is to properly design the drainage borehole pattern in the C1 coal seam of the Tabas coal mine. In this research, the Comsol Multiphysics software was used for numerical modeling of the boreholes. According to the method of diffusion of methane gas in a coal seam, the reduction of methane gas concentration and the amount of gas released from the coal blocks were approximated. For the gas drainage boreholes, the three patterns of the rectangular, parallelogram, and triangular forms were considered. Also, the boreholes were modeled with the three diameters of 76, 86, and 96 mm. This modeling was performed for 180 days of drainage operation and showed that the triangular pattern was more suitable than the other two patterns. The presented model is applicable in coal mines where gas drainage operations are necessary and helps engineers design the patterns of drainage boreholes to maximize their gas drainage efficiency.
    Źródło:
    Journal of Sustainable Mining; 2022, 21, 1; 54--64
    2300-1364
    2300-3960
    Pojawia się w:
    Journal of Sustainable Mining
    Dostawca treści:
    Biblioteka Nauki
    Artykuł
    Tytuł:
    Projektowanie i analiza zastosowań technologii napawania laserowego dla branży lotniczej
    Design and applications analysis of laser cladding technology for aviation industry
    Autorzy:
    Koruba, P.
    Boratyński, T.
    Jurewicz, P.
    Koenig, G.
    Szaroleta, M.
    Reiner, J.
    Chlebus, E.
    Dworak, A.
    Powiązania:
    https://bibliotekanauki.pl/articles/196179.pdf
    Data publikacji:
    2018
    Wydawca:
    Politechnika Rzeszowska im. Ignacego Łukasiewicza. Oficyna Wydawnicza
    Tematy:
    komputerowe wspomaganie procesów
    symulacje multifizyczne
    powłoki funkcjonalne
    regeneracja łopatek
    napawanie hybrydowe
    computer aided process development
    multiphysics simulation
    functional coating
    repair of turbine blades
    hybrid laser cladding
    Opis:
    Technologia napawania laserowego polega na wykorzystaniu wiązki laserowej celem precyzyjnego nałożenia warstwy materiału o podwyższonych właściwościach na podłoże. Szczególne zainteresowanie budzi ona w branży lotniczej. Odpowiednie przygotowanie procesu wiąże się z wykonaniem testów symulacyjnych z wykorzystaniem modeli przepływu dwufazowego oraz interakcji wiązki laserowej z materiałem. Następnie zostają wyznaczone ścieżki ruchu głowicy przy użyciu dedykowanych narzędzi CAD/CAM. W ramach analizy technologii napawania laserowego dla zastosowań branży lotniczej przedstawiono nakładanie powłok funkcjonalnych, będących alternatywą dla chromu elektrolitycznego. Przeanalizowano również metodę regeneracji wierzchołka łopatki turbiny silnika odrzutowego. Zaprezentowano też możliwości obróbki hybrydowej w wytwarzaniu przyrostowym tytanowych komponentów lotniczych oraz metodę monitorowania temperatury celem jakościowej kontroli procesu.
    The laser cladding technology consists of the use of laser beam for precise deposition of a material layer with enhanced properties to the substrate. Therefore it finds special interest in the aviation industry. Appropriate preparation of the process involves performing simulation tests using two-phase flow models and laser beam interaction with material. Subsequently, the laser head movement paths are determined using dedicated CAD/CAM software. In the analysis of laser cladding technology applications for the aviation industry, the deposition of functional coatings, being an alternative to electrolytic chromium, was presented. Secondly, the repair of turbine blade tip was also analyzed. Moreover the capabilities of hybrid laser cladding technology with machining for the additive manufacturing aviation components made of titanium alloys were presented, as well as the method of temperature monitoring for the purpose of qualitative process control implementation.
    Źródło:
    Zeszyty Naukowe Politechniki Rzeszowskiej. Mechanika; 2018, z. 90 [298], 3; 309-321
    0209-2689
    2300-5211
    Pojawia się w:
    Zeszyty Naukowe Politechniki Rzeszowskiej. Mechanika
    Dostawca treści:
    Biblioteka Nauki
    Artykuł
    Tytuł:
    Modelowanie jako narzędzie do zrozumienia i udoskonalenia techniki iskrowego spiekania plazmowego
    Modeling as a tool for understanding and improvement of Spark Plasma Sintering technique
    Autorzy:
    Laptev, A.
    Powiązania:
    https://bibliotekanauki.pl/articles/212178.pdf
    Data publikacji:
    2016
    Wydawca:
    Sieć Badawcza Łukasiewicz - Instytut Obróbki Plastycznej
    Tematy:
    spiekanie plazmowe iskrowe
    spiekanie aktywowane polem elektrycznym
    multifizyka
    modelowanie metodami elementów skończonych
    metoda elementów skończonych
    MES
    rozkład temperatury
    spark plasma sintering
    field assisted sintering
    multiphysics
    finite element modeling
    temperature distribution
    Opis:
    Iskrowe spiekanie plazmowe (SPS) jest nowoczesną metodą prasowania na gorąco bazującą na szybkim nagrzewaniu oporowym. Aktualnie SPS znajduje się w fazie przejściowej pomiędzy pracami badawczo-rozwojowymi a produkcją masową części z proszków metalicznych i ceramicznych. Kluczowym elementem tej metody jest zrozumienie i kontrolowanie rozkładu temperatury wewnątrz narzędzi, w szczególności w wyprasce. Zagadnienie to jest szczególnie ważne przy spiekaniu części wielkogabarytowych, części o złożonej geometrii oraz przy spiekaniu materiałów gradientowych i ogniotrwałych. Wiedza w zakresie pola termicznego pozwala na opracowanie konstrukcji matryc oraz przebiegu procesu spiekania, umożliwiając jednorodny, zdefiniowany rozkład temperatury zależny od aplikacji. W rezultacie, jednorodna lub gradientowa struktura i właściwości mogą zostać osiągnięte. Temperatura nie może być mierzona bezpośrednio wewnątrz wypraski. Dlatego zastosowano metodę elementów skończonych (MES) do numerycznego modelowania rozkładu temperatury. W niniejszym artykule przedstawiono szczegółowo teoretyczne podstawy modelowania. Podkreślono wzajemne oddziaływanie pola elektrycznego, cieplnego i mechanicznego podczas SPS. Przedyskutowano metodologię rozwiązania tego złożonego problemu multifizycznego oraz jego ewentualnego wdrożenia poprzez komercyjne kody MES. Przedstawiono przykład modelowania. Sformułowano perspektywę dla dalszego modelowania. Szczególnie, pole magnetyczne musi być poza tym rozważane podczas modelowania SPS z nagrzewaniem hybrydowym np. z dodatkowym zewnętrznym nagrzewaniem indukcyjnym (nowa hybrydowa koncepcja nagrzewania).
    Spark Plasma Sintering (SPS) is a new hot pressing technique based on the rapid resistive heating. Currently, SPS is in a transition from the R&D phase to the mass production of metallic and ceramic powder parts. The critical point of this technique is understanding and control of temperature field inside the tool and especially in the powder preform. This issue is particularly important at sintering of large-sized parts, parts with a complex geometry and at sintering of functionally graded and refractory materials. The knowledge of temperature field allows the elaboration of die design and sintering cycle profile enabling homogeneous or predefined temperature distribution depending on application. As a result, homogeneous or functionally graded structure and properties can be achieved. The temperature cannot be directly measured inside the powder preform. Therefore, the Finite Element Method (FEM) is used for numerical modeling of the temperature field. In the present paper the theoretical background of modeling is presented in detail. The interaction of electrical, thermal and mechanical fields during SPS is highlighted. The solution methodology for this complex problem of Multiphysics and its possible implementation by commercial FEM codes are discussed. An example on sintering modeling of tungsten-based powder composite is presented. The outlook for further modeling is formulated. Particularly, magnetic field has to be besides considered during the modeling SPS with the hybrid heating i.e. with an additional external inductive heating (new hybrid heating concept).
    Źródło:
    Obróbka Plastyczna Metali; 2016, 27, 3; 223-240
    0867-2628
    Pojawia się w:
    Obróbka Plastyczna Metali
    Dostawca treści:
    Biblioteka Nauki
    Artykuł
    Tytuł:
    Modelowanie złożonej wymiany ciepła w procesie wytwarzania spieku 90W-7Ni-3Fe
    Modelling of complex heat transfer in the 90W-7Ni-3Fe sinter production process
    Autorzy:
    Sypek, J.
    Majewski, T.
    Panas, A.
    Powiązania:
    https://bibliotekanauki.pl/articles/209839.pdf
    Data publikacji:
    2011
    Wydawca:
    Wojskowa Akademia Techniczna im. Jarosława Dąbrowskiego
    Tematy:
    stop 90W-7Ni-3Fe
    spiekanie metali
    metoda rezystancyjna
    wymiana ciepła procesu spiekania
    modelowanie numeryczne
    metoda elementów skończonych
    Comsol Multiphysics
    90W-7Ni-3Fe sinter
    WHA sintering
    resistance heating
    heat transfer at resistance
    sintering
    numerical modelling
    finite element method
    Opis:
    Przedstawiono wyniki analizy numerycznej procesu wytwarzania metalu ciężkiego (spieku ciężkiego) 90W-7Ni-3Fe. Modelowano rzeczywisty układ stosowany do wytwarzania takiego materiału metodą nagrzewania rezystancyjnego. Do budowy modelu i wykonania obliczeń zastosowano pakiet Comsol Multiphysics. Analizę przeprowadzono przy założeniach upraszczających wynikających z ograniczonych możliwości środowiska obliczeniowego i braku pełnych charakterystyk materiałowych w całym analizowanym zakresie temperatury. W modelu odtworzono jednak wszystkie główne zjawiska i uzyskano możliwość jakościowej analizy przebiegu procesu spiekania, identyfikacji problemów technologicznych oraz optymalizacji procesu spiekania rezystancyjnego.
    Results of numerical analysis of 90W-7Ni-3Fe heavy alloy (WHA) production process were presented in the paper. Real system used for production of such material by resistance heating method was modelled applying Comsol Multiphysics FEM software. The analysis was focussed on complex, i.e., combined heat transfer phenomena including phase change effects. Despite some necessary simplifications, all the main phenomena were reconstructed in the numerical model. The numerical modelling enabled for qualitative and quantitative, in some aspect, analyses of the sintering processes and for identification of main technological problems. It also made possible optimisation of the analysed powder metallurgy production process.
    Źródło:
    Biuletyn Wojskowej Akademii Technicznej; 2011, 60, 2; 297-312
    1234-5865
    Pojawia się w:
    Biuletyn Wojskowej Akademii Technicznej
    Dostawca treści:
    Biblioteka Nauki
    Artykuł
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