Informacja

Drogi użytkowniku, aplikacja do prawidłowego działania wymaga obsługi JavaScript. Proszę włącz obsługę JavaScript w Twojej przeglądarce.

English (EN)·Polski (PL)·Yкраїнський (UK)
Przejdź do strony domowej biblioteki Centralna Biblioteka Wojskowa Link otwiera się w nowym oknie Logo biblioteki Prolib Integro - strona głównaCentralna Biblioteka Wojskowa

Wyszukujesz frazę "discrete element method" wg kryterium: Wszystkie pola

  Lista filtrów
Wyrównaj
Wyświetlanie 1-25 z 60
Tytuł:
Strength of industrial sandstones modelled with the Discrete Element Method
Autorzy:
Klejment, Piotr
Dziedziczak, Robert
Łukaszewski, Paweł
Powiązania:
https://bibliotekanauki.pl/articles/2041291.pdf
Data publikacji:
2021
Wydawca:
Politechnika Wrocławska. Oficyna Wydawnicza Politechniki Wrocławskiej
Tematy:
sandstone strength
material resistance
numerical modelling
uniaxial compression strength
Discrete Element Method
ESyS-Particle
Opis:
Sandstone is one of the most popular building materials since the earliest times. It has various textures and colours as well as good technical parameters. Sandstones, having such wide applications, are subjected to various external factors during the period of use. So, it is of utmost importance to have a good knowledge of their strength parameters. We employed a numerical method called Discrete Element Method to examine in a non-invasive manner the mechanical strength of industrial sandstones, that are commonly used as broken stones in road construction, cladding material, paving stones, pavement tiles and so on. Various mechanical external factors were considered, such as breaking, compressional and abrasion forces or impact by external objects and vibrations. Fragmentation of the considered sandstones under compressional regime was a source of knowledge about energy storage inside the material and energy release, as well as appearance of fractures inside the matter and final sandstone fragmentation into crumbs.
Źródło:
Studia Geotechnica et Mechanica; 2021, 43, 4; 346-365
0137-6365
2083-831X
Pojawia się w:
Studia Geotechnica et Mechanica
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
Research on the linear viscoelastic rheological properties of rejuvenated asphalt mastic based on the discrete element method
Autorzy:
Lin, Mei
Lei, Yu
Li, Ping
Shuai, Jun
Wang, Zhaoli
Powiązania:
https://bibliotekanauki.pl/articles/27312105.pdf
Data publikacji:
2023
Wydawca:
Polska Akademia Nauk. Czasopisma i Monografie PAN
Tematy:
model konstytutywny
metoda elementów dyskretnych
mastyks asfaltowy odnowiony
właściwości reologiczne
constitutive model
discrete element method
rejuvenated asphalt mastic
rheological characteristics
Opis:
The rheological property of asphalt is an important factor affecting the pavement performance of asphalt binder, and the fundamental reason for the change of asphalt rheological property is the strong evolution of asphalt material meso structure. However, the internal mechanism of rejuvenated asphalt mastic system is complex and its rules are difficult to grasp. Aiming to study the relationship between meso mechanical parameters and rheological parameters of rejuvenated asphalt mastic, the meso structure model of rejuvenated asphalt mastic was established and improved based on the discrete element method. Moreover, the meso parameters of the model were obtained by the objective function method, and then the influences of various factors were studied to construct the mathematical constitutive model of rheological parameter modulus and meso mechanical parameters. Combing with the reliability of the improved Burgers model was verified based on the rheological test results of rejuvenated asphalt mastic. In addition, the virtual test of dynamic shear rheological dynamic frequency scanning was carried out on the asphalt mastic sample by particle flow software. By adjusting the mesomechanical parameters, the simulation results (complex shear modulus and phase angle) were consistent with the test results. This study clarified the relationship between mesomechanics and macro performance, and this model could be used to obtain the complex shear modulus of rejuvenated asphalt mastic under different types, filler-asphalt ratio and external force environments by adjusting particle flow, wall boundary and other conditions, which can greatly save the workload for the later research and provide a theoretical basis for production experiments.
Źródło:
Archives of Civil Engineering; 2023, 69, 2; 399--416
1230-2945
Pojawia się w:
Archives of Civil Engineering
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
Influence of Rolling Friction Coefficient on Inter-Particle Percolation in a Packed Bed by Discrete Element Method
Autorzy:
Zhou, H.
Luo, Z.
Zhang, T.
You, Y.
Li, H.
Zou, Z.
Powiązania:
https://bibliotekanauki.pl/articles/356261.pdf
Data publikacji:
2016
Wydawca:
Polska Akademia Nauk. Czytelnia Czasopism PAN
Tematy:
inter-particle percolation
rolling friction coefficient
discrete element method;
percolation velocity
dispersion coefficient
Opis:
Rolling friction representing the energy dissipation mechanism with the elastic deformation at the contact point could act directly on particle percolation. The present investigation intends to elucidate the influence of rolling friction coefficient on inter-particle percolation in a packed bed by discrete element method (DEM). The results show that the vertical velocity of percolating particles decreases with increasing the rolling friction coefficient. With the increase of rolling friction coefficient, the transverse dispersion coefficient decreases, but the longitudinal dispersion coefficient increases. Packing height has a limited effect on the transverse and longitudinal dispersion coefficient. In addition, with the increase of size ratio of bed particles to percolation ones, the percolation velocity increases. The transverse dispersion coefficient increases with the size ratio before D/d<14. And it would keep constant when the size ratio is greater than 14. The longitudinal dispersion coefficient decreases when the size ratio increases up to D/d=14, then increases with the increase of the size ratio. External forces affect the percolation behaviours. Increasing the magnitude of the upward force (e.g. from a gas stream) reduces the percolation velocity, and decreases the dispersion coefficient.
Źródło:
Archives of Metallurgy and Materials; 2016, 61, 4; 1795-1804
1733-3490
Pojawia się w:
Archives of Metallurgy and Materials
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
Mechanical analysis and research of the conveyor belt of plane turning belt conveyor based on discrete element method
Autorzy:
Li, D. Y.
Wang, S.
Hu, K.
Powiązania:
https://bibliotekanauki.pl/articles/224069.pdf
Data publikacji:
2017
Wydawca:
Polska Akademia Nauk. Czytelnia Czasopism PAN
Tematy:
przenośnik taśmowy
siła taśmy przenośnikowej
metoda elementów dyskretnych
optymalizacja
belt conveyor
conveyor belt force
Discrete Element Method
optimization design
Opis:
In view of the size and the change of the load force of the conveyor belt at the turning point of the plane turning belt conveyor, the influencing factors of the stress of the conveyor belt at the turning point of the plane turning belt conveyor under full load condition are analyzed. A three dimensional model of the turning point of the plane turning belt conveyor is established. Combined with previous research experience, the formula for calculating the load is put forward. Based on discrete element method, multiple sets of internal curve elevation angle and the belt speed are used for dynamic simulation analysis. The results showed that the middle of conveyor belt is the most stressed, the lateral force second, the force of the inner conveyor belt is the least. Outside force increases with the increase of speed; there is no change in the middle band; the inner band force decreases with the increase of the velocity. Outside force decreases with the decrease of the inclination angle. With the change of the inclination angle, the force is basically unchanged. With the decreasing of the inclination angle, the force increases gradually. By optimizing the design parameters of the plane turning belt conveyor, the force of belt is reduced, and the service life of belt is improved.
Źródło:
Archives of Transport; 2017, 41, 1; 55-62
0866-9546
2300-8830
Pojawia się w:
Archives of Transport
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
Próba zastosowania metody elementów dyskretnych w mechanice ciała stałego
An attempt to use Discrete Element Method in solid mechanics
Autorzy:
Nowicki, T.
Powiązania:
https://bibliotekanauki.pl/articles/390929.pdf
Data publikacji:
2016
Wydawca:
Politechnika Lubelska. Wydawnictwo Politechniki Lubelskiej
Tematy:
metoda elementów dyskretnych (odosobnionych)
ESys-Particle
skala mezo
discrete element method
mesoscale
Esys-Particle
Opis:
Praca poświęcona jest metodzie elementów dyskretnych. W chwili obecnej jest to metoda numeryczna służąca do modelowanie materiałów, głównie skał. W pracy zawarto opis najprostszej wersji metody. Przedstawiono również przeprowadzoną symulację komputerową z zastosowaniem pakietu obliczeniowego ESys-Particle. Artykuł należy traktować jako wprowadzenie do prac nad zastosowaniami tej metody w inżynierii budowlanej.
The paper is devoted to Discrete Element Method. Currently the method is mainly used for mechanics of rock. The paper contains the description of the simplest version of the method. Computer simulation using Esys-Particle computer code is presented. The paper is an introduction to the study on the method applications to building engineering.
Źródło:
Budownictwo i Architektura; 2016, 15, 4; 153-162
1899-0665
Pojawia się w:
Budownictwo i Architektura
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
Feeder type optimisation for the plain flow discharge process of an underground hopper by discrete element modelling
Autorzy:
Necas, J.
Hlosta, J.
Zurovec, D.
Zidek, M.
Rozbroj, J.
Zegzulka, J.
Powiązania:
https://bibliotekanauki.pl/articles/101876.pdf
Data publikacji:
2017
Wydawca:
Stowarzyszenie Inżynierów i Techników Mechaników Polskich
Tematy:
drag chain conveyor
discrete element method
simulation
Opis:
This paper describes optimisation of a conveyor from an underground hopper intended for a coal transfer station. The original solution was designed with a chain conveyor encountered operational problems that have limited its continuous operation. The Discrete Element Modeling (DEM) was chosen to optimise the transport. DEM simulations allow device design modifications directly in the 3D CAD model, and then the simulation makes it possible to evaluate whether the adjustment was successful. By simulating the initial state of coal extraction using a chain conveyor, trouble spots were identified that caused operational failures. The main problem has been the increased resistance during removal of material from the underground hopper. Revealed resistances against material movement were not considered in the original design at all. In the next step, structural modifications of problematic nodes were made. For example, the following changes have been made: reduction of storage space or installation of passive elements into the interior of the underground hopper. These modifications made were not effective enough, so the type of the conveyor was changed from a drag chain conveyor to a belt conveyor. The simulation of the material extraction using a belt conveyor showed a significant reduction in resistance parameters while maintaining the required transport performance.
Źródło:
Advances in Science and Technology. Research Journal; 2017, 11, 3; 246-252
2299-8624
Pojawia się w:
Advances in Science and Technology. Research Journal
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
Effect of Aspect Ratio on Iron-Ore Briquettes During Twin-Roll Briquetting
Autorzy:
Kim, Kang-Min
Bae, Jong-Ho
Han, Jeong-Whan
Powiązania:
https://bibliotekanauki.pl/articles/355616.pdf
Data publikacji:
2020
Wydawca:
Polska Akademia Nauk. Czytelnia Czasopism PAN
Tematy:
numerical analysis
discrete element method
roll briquetting
Opis:
In the ironmaking, sizes of raw materials such as iron ores and coke must be adjusted for subsequent process in the blast furnace. The depletion of high grade iron ore in recent years necessitates a technology that can utilize low-grade fine iron ores. Thus, steelmakers have been studying the sinter-briquette complex firing process that employs a method of charging the sinter feed together with briquettes made of fine iron ore. In this process, larger briquettes increase the briquette productivity per unit time but decrease the green strength of briquettes and they can break during transportation and charging. Thus, the briquette shape is very important. Therefore, in this study, we simulate a twin roll briquetting process using the DEM analysis and compared the compressive force distributions in the briquette for different aspect ratios. This study is a new attempt, because research cases by numerical methods on the same or similar systems are very rare. Consequently, the optimal aspect ratio is 0.5 at briquette height 20 mm, 2.0 at 30 mm, and 1.5 at 40 mm. Also, the average compressive force increased in proportion with the pocket height at the sameaspect ratio. Therefore, to increase the pocket depth for high productivity, the pocket height must also be increased for obtaining high strength briquettes.
Źródło:
Archives of Metallurgy and Materials; 2020, 65, 4; 1335-1339
1733-3490
Pojawia się w:
Archives of Metallurgy and Materials
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
Effect of Deflector Plate for Particle Size Segregation Control
Autorzy:
Kim, Kang-Min
Kim, Ju-Hun
Kwon, Jae-Hong
Lee, Ji-A
Han, Jeong-Whan
Powiązania:
https://bibliotekanauki.pl/articles/353855.pdf
Data publikacji:
2019
Wydawca:
Polska Akademia Nauk. Czytelnia Czasopism PAN
Tematy:
size segregation
numerical analysis
discrete element method
Opis:
In general, uniform mixing of particles is desirable in the process of particle handling. However, during the charging of sinter feed and upper ore, size segregation must be induced to prevent heat imbalance, ensure bed permeability, and prevent the loss of fine ore. In this study, upper ore charging was simulated using a discrete element method (DEM) to find the optimal method for controlling particle size segregation, and the segregation characteristics in the upper ore bed were investigated when a deflector plate was applied to the charging machine. The degree of vertical segregation increased when a deflector plate was applied, and it was confirmed that the segregation direction in the upper ore bed can be controlled by adjusting the charging direction of the upper ore by using a deflector plate. In order to apply this method directly to the actual process, further study is needed to understand the influence of the characteristics of the deflector plate such as length and angle.
Źródło:
Archives of Metallurgy and Materials; 2019, 64, 2; 495-500
1733-3490
Pojawia się w:
Archives of Metallurgy and Materials
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
The possibility of determining the input parameters for the Discrete Element Method
Sposób ustalania parametrów wejściowych dla Metody Elementów Dyskretnych
Autorzy:
Rozbroj, J.
Zegzulka, J.
Jezerska, L.
Necas, J.
Zurovec, D.
Powiązania:
https://bibliotekanauki.pl/articles/318282.pdf
Data publikacji:
2015
Wydawca:
Polskie Towarzystwo Przeróbki Kopalin
Tematy:
metoda elementów dyskretnych (DECS)
pomiar tarcia
kąt tarcia statycznego
tarcie obrotowe
tarcie toczne
restytucja
parametry wejściowe
Discrete Element Method (DEM)
friction measurement
angle of static friction
rolling friction
restitution
input parameters
Opis:
This article describes measurements of mechanical-physical properties of a particular material, which can be used for validation or calibration of Discreet Element Method (DEM) and definition of basic input parameters or their extents. The validation can be executed by means of a real model of the equipment with which the DEM model is compared. It also explains potential measurement procedures for a real material to determine and verify the input parameter properties for the DEM. The validation material can be of plastic spherical particles, because this shape represents the basic particle for the DEM. Determination of the coefficient of restitution is executed by means of a high-speed camera and subsequent measurement of the particle's movement on a single XY plane. Collection of the measured data is used for identification and selection of suitable input friction parameters for the DEM. All procedures mentioned in this article can lead to clarification of validation or calibration, thus facilitating development and design of new equipment with application of DEM in the future.
Ten artykuł opisuje możliwości pomiaru właściwości mechanicznych i fizycznych masy cząstek stałych, które mogą być wykorzystane do walidacji i kalibracji DEM, a służy również do definiowania podstawowych parametrów wejściowych, lub ich zakresów. Walidacja może być przeprowadzona za pomocą realistycznego modelu urządzenia, który porównuje się z modelu DEM. Dalej oto lista możliwych procedur pomiaru realistycznego materiału prowadzące do identyfikacji i weryfikacji właściwości parametrów wejściowych dla DEM. Jako materiał walidacji mogą być stosowane plastikowe kuliste cząstki, ponieważ ten kształt stanowi zasadniczą cząstkę dla DEM. Wyznaczanie współczynnika restytucji jest realizowany za pomocą kamery o wysokiej prędkości, a następ-nie mierzy się ścieżka ruchu cząstek w jednej płaszczyźnie XY. Zbieranie danych pomiarowych jest używany do identyfikacji i doboru odpowiednich parametrów wejściowe tarcia dla DEM. Wszystkie procedury wymienione w tym artykule może doprowadzić do wyjaśnienia problemów walidacji i kalibracji, i w ten sposób ułatwić rozwój i projektowanie nowych urządzeń w przyszłości przy użyciu DEM.
Źródło:
Inżynieria Mineralna; 2015, R. 16, nr 1, 1; 109-114
1640-4920
Pojawia się w:
Inżynieria Mineralna
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
Determination of mechanical properties for wood pellets used in DEM simulations
Autorzy:
Gallego, E.
Fuentes, J.M.
Ruiz, A.
Hernandez-Rodrigo, G.
Aguado, P.
Ayuga, F.
Powiązania:
https://bibliotekanauki.pl/articles/2082921.pdf
Data publikacji:
2020
Wydawca:
Polska Akademia Nauk. Instytut Agrofizyki PAN
Tematy:
biomass
wood pellets
mechanical properties
discrete element method
Opis:
Wood pellets are increasingly being used to produce energy as a part of the decarbonization process of the economy, but their handling is associated with several problems, which usually requires that the equipment used has to be modified and improved. The discrete element method is a numerical technique suitable for simulating individual particles and handling systems. This paper focuses on the determination of the mechanical and physical parameters for wood pellet particles which are required to develop a discrete element method model to improve handling and transport systems. This study reports the experimentally determined values for wood pellet particles with respect to particle density, modulus of elasticity, particle – particle and particle – wall coefficients of restitution, and particle – particle and particle – wall coefficients of friction. Following the previous findings by other researchers with large samples of bulk material, it has been found that the modulus of elasticity for individual wood pellets depends on the water content, and the particle – wall coefficient of restitution depends on the impact velocity.
Źródło:
International Agrophysics; 2020, 34, 4; 485-494
0236-8722
Pojawia się w:
International Agrophysics
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
Optimization of a screw conveyors exploitation parameters
Autorzy:
Karwat, Bolesław
Rubacha, Piotr
Stańczyk, Emil
Powiązania:
https://bibliotekanauki.pl/articles/1841744.pdf
Data publikacji:
2021
Wydawca:
Polska Akademia Nauk. Polskie Naukowo-Techniczne Towarzystwo Eksploatacyjne PAN
Tematy:
screw conveyor
discrete element method
bulk material
exploitation characteristics
Opis:
The paper describes the problem of designing screw conveyors in terms of determining their exploitation characteristics. Based on the actual values of mass efficiency and power demand obtained in a laboratory experiment, the theoretical design methods and the numerical discrete element method model results were verified. The obtained results have shown that the currently used theoretical methods underestimate the mass efficiency and power demand compared to experiments when typical values of filling rate coefficient and progress resistance coefficient are used. It was also shown that the results of DEM simulations are in good agreement with the experiments in terms of mass efficiency and power demand. Based on the exploitation characteristics determined in DEM simulations for different constructions of the screw and different rotational speeds, multi-objective optimization of the exploitation parameters of the screw was performed in order to minimize the power demand of a screw conveyor and simultaneously maximize its mass efficiency. The optimization results showed that it is possible to find such construction and the rotational speed that will maximize the mass efficiency of the conveyor and keep the power demand low, reducing the exploitation costs of the device.
Źródło:
Eksploatacja i Niezawodność; 2021, 23, 2; 285-293
1507-2711
Pojawia się w:
Eksploatacja i Niezawodność
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
Numerical simulations of the exploitation parameters of the rotary feeder
Autorzy:
Karwat, Bolesław
Rubacha, Piotr
Stańczyk, Emil
Powiązania:
https://bibliotekanauki.pl/articles/27315596.pdf
Data publikacji:
2022
Wydawca:
STE GROUP
Tematy:
bulk materials
Discrete Element Method
exploitation characteristics rotary feeder
Opis:
The article presents the problems of determining the mass efficiency of a rotary feeder depending on the selection of design parameters of the device, such as outer diameter, number of blades and rotational speed of the rotor. The hitherto theoretical methods of calculating the feeder efficiency were presented, as well as a new method of determining the device operation parameters was proposed. For this purpose, the numerical Discrete Element Method was used, which allowed simulating the transport of limestone powder in a cell feeder with various design variants. The results of the tests showed that the above design parameters affect the instantaneous efficiency of the feeder and thus impact the distribution of the dosed material during the operation of the device. Depending on the design solution, the simulation results gave information on the fill factor of the feeders. The study showed a significant potential of DEM simulation in the design of circular feeders intended for dosing bulk materials.
Źródło:
Management Systems in Production Engineering; 2022, 4 (30); Bibliogr. 33 poz., rys., tab.
2299-0461
Pojawia się w:
Management Systems in Production Engineering
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
A new approach for obtaining the geometric properties of a granular porous bed based on DEM simulations
Autorzy:
Sobieski, W.
Dudda, W.
Lipiński, S.
Powiązania:
https://bibliotekanauki.pl/articles/297977.pdf
Data publikacji:
2016
Wydawca:
Uniwersytet Warmińsko-Mazurski w Olsztynie
Tematy:
granular beds
spatial structure
Discrete Element Method
PathFinder code
Opis:
In the article, a new way for obtaining a set of geometrical parameters of granular porous beds is presented, if the data on the locations and sizes of all particles is available. The input data were prepared with the use of Discrete Element Method. The other way for acquiring the input data may be the application of Computed Tomography (CT) and Image Analysis (IA) techniques. All geometrical parameters are calculated with the use of own numerical code called PathFinder (freely available in the Internet together with its source code). In addition to description of the method of calculations, two examples of its use are presented. One simulation was performed in PFC3D code, and the other in YADE software. The aim of the article was to show clearly that a porosity is not sufficient to describe the spatial structure of a porous body. In both presented examples, the porosity value is almost the same, but other parameters, e.g. tortuosity, are different. The motivation to write the PathFinder code were significant problems with obtaining geometrical parameters needed in investigations related to granular porous media. The issues described in the article are a part of an overall research methodology relating to the linking the micro- and macro-scale investigations of granular porous beds. The areas of applications of this methodology are not discussed in the article.
Źródło:
Technical Sciences / University of Warmia and Mazury in Olsztyn; 2016, 19(2); 165-187
1505-4675
2083-4527
Pojawia się w:
Technical Sciences / University of Warmia and Mazury in Olsztyn
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
The vertical screw conveying characteristics of cohesive particle and optimization of design parameters
Autorzy:
Chen, Suifan
Zhang, Xiaomeng
Li, Qipeng
Shen, Ce
Shi, Yongchang
Powiązania:
https://bibliotekanauki.pl/articles/24200814.pdf
Data publikacji:
2023
Wydawca:
Polska Akademia Nauk. Polskie Naukowo-Techniczne Towarzystwo Eksploatacyjne PAN
Tematy:
discrete element method
conveying characteristics
NSGA-II
comprehensive evaluation
Opis:
The purpose of this paper is to solve the problem of low conveying efficiency and serious blade wear during vertical screw conveying of cohesive particles. Firstly, the reliability of DEM simulation was verified by comparing the simulated and theoretical values and the influence regularity of different design parameters (rotational speed, pitch, and clearance) on screw conveying characteristics were analyzed based on DEM. In addition, the effect of design parameters on the screw conveying characteristics is identified by ANOVA. Then, the multi-objective optimization model with the both of maximizing the average mass flow rate and minimizing the maximum wear depth of the blade was established using the polynomial fitting regression, which was solved by the non-dominated sorting genetic algorithm (NSGA-II). Finally, the comprehensive evaluation was used to determine the best design parameters. The above research results provide a certain reference for the study of cohesive particle’s vertical screw conveying characteristics and equipment optimization design.
Źródło:
Eksploatacja i Niezawodność; 2023, 25, 1; art. no. 13
1507-2711
Pojawia się w:
Eksploatacja i Niezawodność
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
Analysis of conveyor belt wear caused by material acceleration in transfer stations
Autorzy:
Doroszuk, Błażej
Król, R.
Powiązania:
https://bibliotekanauki.pl/articles/89064.pdf
Data publikacji:
2019
Wydawca:
Politechnika Wrocławska. Wydział Geoinżynierii, Górnictwa i Geologii. Instytut Górnictwa
Tematy:
conveyor transfer station
discrete element method
acceleration length
abrasive wear
Opis:
In conveyor transport systems, different solutions to the transfer points constructions are used. Choosing the right solution requires conditions analysis of the cooperation between two conveyors. For years, the analytical methods have been used to evaluate the discharge trajectory of the transported material. Increasingly, to evaluate the movement of grains in the transfer space to analyze the behavior of the bulk material in contact with transfer chute elements, researchers successfully use simulations performed in the discrete element method (DEM). Well-constructed chute allows the material stream to be uniformly fed onto the receiving conveyor with a desired stable tangential speed. Proper design reduces motion resistances and belt wear. In the paper, the analysis of selected construction solutions of transfer points and the possibilities of their usage in copper ore transport systems were performed. The research was conducted using the DEM simulations of the ore flow. For specifying the best conditions of the cooperation of the feeding and receiving conveyors, a series of simulations were generated. The criteria for the comparative evaluation of the analyzed solutions were the values of acceleration zone length and abrasive wear of the belt.
Źródło:
Mining Science; 2019, 26; 189-201
2300-9586
2353-5423
Pojawia się w:
Mining Science
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
3D DEM simulations of basic geotechnical tests with early detection of shear localization
Autorzy:
Grabowski, Aleksander
Nitka, Michał
Powiązania:
https://bibliotekanauki.pl/articles/1845158.pdf
Data publikacji:
2021
Wydawca:
Politechnika Wrocławska. Oficyna Wydawnicza Politechniki Wrocławskiej
Tematy:
direct shear
granular material
discrete element method
localization
grain level
Opis:
This paper deals with elementary geotechnical tests: triaxial and direct shear of cohesionless sand using the discrete element method (DEM). The capabilities of the numerical DEM code are shown, with a special focus on the early phenomena appearance in localization zones. The numerical tests were performed in 3D conditions with spherical grains. Contact moments law was introduced due to simulate not perfectly round sand grains. The influence of different physical parameters was studied, e.g. initial density or confining pressure. The sieve curve corresponded to the Karlsruhe sand [1]; however, in some tests, it was linearly scaled. Special attention was laid on the behaviour of the sand grains inside localization, e.g. rotation, porosity, fluctuations, etc. and forces redistribution. Emphasis was given on the pre-failure regime and early localization predictors.
Źródło:
Studia Geotechnica et Mechanica; 2021, 43, 1; 48-64
0137-6365
2083-831X
Pojawia się w:
Studia Geotechnica et Mechanica
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
Implementation of a viscoelastic boundary condition to Yade – open source DEM software
Autorzy:
Brzeziński, Karol
Zbiciak, Artur
Gladky, Anton
Powiązania:
https://bibliotekanauki.pl/articles/2200894.pdf
Data publikacji:
2023
Wydawca:
Polskie Towarzystwo Mechaniki Teoretycznej i Stosowanej
Tematy:
Discrete Element Method
viscoelastic boundary condition
granular layer
pavement subsoil
Opis:
The paper presents implementation of a viscoelastic boundary condition to Yade software. The implemented boundary condition constraints linear displacements of bodies by applying a reaction force resulting from a solution of the Burgers rheologicalmodel. This work presents the results of one of validation tests, where the output of Discrete Element Simulation (DEM) was compared with an analytically formulated soft-contact problem. Furthermore, potential application in more complex simulations (plate load test) is demonstrated. It shows that the proposed approach allows for realistic yet efficient modeling of foundations purely within the DEM framework.
Źródło:
Journal of Theoretical and Applied Mechanics; 2023, 61, 2; 355--364
1429-2955
Pojawia się w:
Journal of Theoretical and Applied Mechanics
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
Particle shape effect on macroscopic behaviour of underground structures: numerical and experimental study
Autorzy:
Szarf, K.
Combe, G.
Villard, P.
Powiązania:
https://bibliotekanauki.pl/articles/178734.pdf
Data publikacji:
2014
Wydawca:
Politechnika Wrocławska. Oficyna Wydawnicza Politechniki Wrocławskiej
Tematy:
discrete element method
particle shape
underground pipe
digital image correlation
Opis:
The mechanical performance of underground flexible structures such as buried pipes or culverts made of plastics depend not only on the properties of the structure, but also on the material surrounding it. Flexible drains can deflect by 30% with the joints staying tight, or even invert. Large deformations of the structure are difficult to model in the framework of Finite Element Method, but straightforward in Discrete Element Methods. Moreover, Discrete Element approach is able to provide information about the grain–grain and grain–structure interactions at the microscale. This paper presents numerical and experimental investigations of flexible buried pipe behaviour with focus placed on load transfer above the buried structure. Numerical modeling was able to reproduce the experimental results. Load repartition was observed, being affected by a number of factors such as particle shape, pipe friction and pipe stiffness.
Źródło:
Studia Geotechnica et Mechanica; 2014, 36, 3; 67-74
0137-6365
2083-831X
Pojawia się w:
Studia Geotechnica et Mechanica
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
The effect of ball size distribution on power draw, charge motion and breakage mechanism of tumbling ball mill by discrete element method (DEM) simulation
Autorzy:
Panjipour, R.
Barani, K.
Powiązania:
https://bibliotekanauki.pl/articles/110020.pdf
Data publikacji:
2018
Wydawca:
Politechnika Wrocławska. Oficyna Wydawnicza Politechniki Wrocławskiej
Tematy:
discrete element method
ball mill
ball size distribution
mill power
breakage mechanism
Opis:
In this research, the effect of ball size distribution on the mill power draw, charge motion regime and breakage mechanism in a laboratory ball mill was studied using the discrete element method (DEM) simulation. The mill shell and crushing balls were made of Plexiglas® and compressed glass, respectively. Modeling was performed using Particle Flow Code 3D (PFC3D). Model parameters were back-calculated by comparing the power draws and images obtained from simulation and laboratory test works. After determining the model parameters, the mill was simulated in mill fillings of 15, 20, 25, 30, 35 and 40% with ball media of 2 and 2.5 cm in diameter. For every mill filling, the numbers of big and small balls were changed and 11 scenarios were chosen. The results showed that at a constant mill filling, the power draw was changed with changing the ball size distribution and for all mill fillings the maximum power draw occurred when the fraction of small balls was between 30-40%. The effect of ball size distribution increased with increasing mill filling and for the mill filling of 35%, the ball size distribution had the maximum effect on the power draw. When the mill charge contained mono-sized balls, the ball flow regime inside the mill transited to the cataracting and impact breakage was the main breakage mechanism. Increasing the fraction of big balls from 0 to 70% led the flow of balls into the cascading regime and breakage mechanism to attrition.
Źródło:
Physicochemical Problems of Mineral Processing; 2018, 54, 2; 258-269
1643-1049
2084-4735
Pojawia się w:
Physicochemical Problems of Mineral Processing
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
Validation of movement over a belt conveyor drum
Autorzy:
Rozbroj, J.
Necas, J.
Gelnar, D.
Hlosta, J.
Zegzulka, J.
Powiązania:
https://bibliotekanauki.pl/articles/101900.pdf
Data publikacji:
2017
Wydawca:
Stowarzyszenie Inżynierów i Techników Mechaników Polskich
Tematy:
Discrete Element Method
belt conveyor
Particle Image Velocimetry
trajectory of particles
Opis:
This paper presents the use of new modern methods for the research of movement of material on a belt conveyor. One of the innovative methods is Particle Image Velocimetry (PIV), which was used to scan and assess the two-dimensional vector field of speed of particles on the belt conveyor. Outputs from PIV were compared to simulations of the same transport process. These simulations were performed using the Discrete Element Method (DEM). Four transport speeds of material were assessed for a real and simulative belt conveyor model. Software tracking of particle movement was used to determine and compare the trajectories of paths of particles leaving the belt conveyor drum. Validation of the DEM simulation of material movement over a belt conveyor drum using PIV provided acceptable results in the area of particle speed fields. Comparison of the particle path trajectory corresponds to the preliminary hypothesis which leads to calibration of the DEM simulation. The results and assessment of this paper were created based on validation.
Źródło:
Advances in Science and Technology. Research Journal; 2017, 11, 2; 118-124
2299-8624
Pojawia się w:
Advances in Science and Technology. Research Journal
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
Simulation of powder sintering using a discrete element model
Autorzy:
Rojek, J.
Nosewicz, S.
Pietrzak, K.
Chmielewski, M.
Powiązania:
https://bibliotekanauki.pl/articles/386478.pdf
Data publikacji:
2013
Wydawca:
Politechnika Białostocka. Oficyna Wydawnicza Politechniki Białostockiej
Tematy:
powder sintering
simulation
discrete element method
spiekanie proszków
symulacja
metoda elementów dyskretnych
Opis:
This paper presents numerical simulation of powder sintering. The numerical model introduced in this work employs the discrete element method which assumes that material can be modelled by a large assembly of discrete elements (particles) of spherical shape interacting among one another. Modelling of sintering requires introduction of the cohesive interaction among particles representing inter-particle sintering forces. Numerical studies of sintering have been combined with experimental studies which provided data for calibration and validation of the model. In the laboratory tests evolution of microstructure and density during sintering have been studied. Comparison of numerical and experimental results shows a good performance of the numerical model developed.
Źródło:
Acta Mechanica et Automatica; 2013, 7, 3; 157-179
1898-4088
2300-5319
Pojawia się w:
Acta Mechanica et Automatica
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
Numeryczne analizy bezpośredniego ścinania gruntu niespoistego z zastosowaniem metody elementów dyskretnych
Numerical analyses of the direct shearing of non-cohesive soil using the discrete element method
Autorzy:
Szklennik, P.
Powiązania:
https://bibliotekanauki.pl/articles/402753.pdf
Data publikacji:
2012
Wydawca:
Politechnika Białostocka. Oficyna Wydawnicza Politechniki Białostockiej
Tematy:
bezpośrednie ścinanie
metoda elementów dyskretnych
symulacja numeryczna
discrete element method
shearing
numerical analysis
Opis:
W pracy przedstawiono rezultaty symulacji numerycznych przebiegu bezpośredniego ścinania gruntu niespoistego z wykorzystaniem modelu metody elementów dyskretnych 2D. Identyfikację parametrów kontaktu elementów przeprowadzono w dwóch etapach. W pierwszej kolejności ustalono parametry określające maksymalne opory tarcia, następnie zweryfikowano odpowiednie wartości poszczególnych modułów sztywności. Poprzez porównanie rezultatów symulacji z wynikami testów laboratoryjnych oraz wartościami kąta tarcia wewnętrznego dostępnymi w literaturze wykazano możliwość symulacji przebiegu ścinania gruntów o różnym uziarnieniu.
The paper presents results of the numerical simulations of the direct shearing of non-cohesive soil using two-dimensional discrete element method. Identification of contact stiffness parameters as well as sliding and rolling friction coefficients was the main subject of the work. Grain roughness and its shape effect were simulated by increasing friction parameters. Internal friction angles obtained by the numerical calculations were compared with the results of the laboratory tests and the values from the literature sources. It was shown that it is possible to simulate shear strength of soil samples with various grain size distribution using the discrete element method simplified to two dimensions.
Źródło:
Budownictwo i Inżynieria Środowiska; 2012, 3, 4; 211-216
2081-3279
Pojawia się w:
Budownictwo i Inżynieria Środowiska
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
CFD-DEM simulation of raceway size and mechanical characteristics of industrial scale blast furnace
Autorzy:
Gao, Yuzhen
Chan, Choon Kit
Powiązania:
https://bibliotekanauki.pl/articles/27315659.pdf
Data publikacji:
2023
Wydawca:
Zachodniopomorski Uniwersytet Technologiczny w Szczecinie. Wydawnictwo Uczelniane ZUT w Szczecinie
Tematy:
raceway
CFD-DEM
Computional Fluid Dynamics
Discrete Element Method
numerical simulation
blast furnace
Opis:
The raceway plays a crucial role in ensuring the stable functioning of the ironmaking blast furnace. It is the key site where the chemical reaction of coke combustion takes place, providing the necessary heat and reducing gas for the upper iron ore reduction process. Consequently, the size of the raceway serves as an essential indicator of the blast furnace’s operational condition. In this study, a mathematical model for the raceway of an industrial-scale blast furnace was established. Extensive innovation investigations were conducted to explore the characteristics pertaining to the raceway’s size. The simulation outcomes demonstrate that both the particle size and the inlet velocity exert significant influences on the raceway dimensions. Specifically, the height of the raceway is predominantly affected by the particle size, whereas the inlet velocity predominantly influences the depth of the raceway.
Źródło:
Polish Journal of Chemical Technology; 2023, 25, 3; 71--78
1509-8117
1899-4741
Pojawia się w:
Polish Journal of Chemical Technology
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
Analiza numeryczna interakcji modelowej obudowy tunelowej z gruntem niespoistym
Numerical analysis of interaction between a model tunnel lining and non-cohesive soil
Autorzy:
Szklennik, Paweł
Powiązania:
https://bibliotekanauki.pl/articles/211264.pdf
Data publikacji:
2019
Wydawca:
Wojskowa Akademia Techniczna im. Jarosława Dąbrowskiego
Tematy:
budownictwo
metoda elementów dyskretnych
obudowa walcowa
civil engineering
discrete element method
tunnel lining
Opis:
W pracy przedstawiono numeryczną analizę interakcji modelowej obudowy tunelowej z otaczającym niespoistym ośrodkiem gruntowym. Analizy dokonano, przeprowadzając symulacje z wykorzystaniem autorskiego programu opartego na metodzie elementów dyskretnych. Wykorzystano model skalibrowany wcześniej na podstawie badań laboratoryjnych przez porównanie deformacji obudowy występujących w badaniu i symulacji numerycznej. Dla tak ustalonego modelu przeprowadzono szereg symulacji przy konstrukcji obudowy zarówno wiotkiej, jak i sztywnej. Badano obciążenia działające na obudowę, rozkład naprężeń w ośrodku gruntowym otaczającym konstrukcję oraz przemieszczenia jego cząstek. Analizy przeprowadzono przy działaniu ciężaru gruntu oraz obciążenia technologicznego zadawanego z powierzchni. Analizowano modele z nadkładem gruntu równym jednej średnicy i dwóm średnicom obudowy. Wartości uzyskiwanych numerycznie obciążeń obudowy porównano z obliczonymi według metody Hewetta. Wykazano, że obciążenia te oraz naprężenia w gruncie są istotnie powiązane ze sztywnością obudowy i w związku z tym mogą znacznie odbiegać od standardowo przyjmowanych dla takich konstrukcji sytuacji obciążeniowych.
The paper presents an analysis and assessment of an interaction between a model tunnel lining and surrounding non-cohesive soil. The analysis was conducted with numerical simulations using the author’s program based on an algorithm of the discrete element method. Previously calibrated numerical model was used in the calculations. Calibration was based on comparison of the construction deformations observed in the laboratory tests and during the simulation. Numerous simulations, performed in the calibrated numerical model, included calculations for a flexible and rigid construction of the lining. The tunnel construction loads, stress distribution in the surrounding soil, and soil particles’ displacements were investigated. Analyses were conducted in two variants - when only soil weight is acting on the tunnel construction and when the external load transmitted from the surface is present. Also two variants of the backfill height were investigated - they were equal to one and two diameters of the tunnel. The values of tunnel loads, which were numerically calculated, were compared with the corresponding values, calculated by the Hewett’s method. It is shown that distribution of tunnel loads and stresses in the surrounding soil is strongly linked with the tunnel construction stiffness, thus it can be significantly different from standard load situations for such constructions.
Źródło:
Biuletyn Wojskowej Akademii Technicznej; 2019, 68, 1; 175-195
1234-5865
Pojawia się w:
Biuletyn Wojskowej Akademii Technicznej
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
Prognoza redukcji ciśnienia wybuchu warstwą materiału ziarnistego
Prediction of reduction of blast load pressure by granular medium layer
Autorzy:
Szklennik, P.
Powiązania:
https://bibliotekanauki.pl/articles/209360.pdf
Data publikacji:
2016
Wydawca:
Wojskowa Akademia Techniczna im. Jarosława Dąbrowskiego
Tematy:
ośrodek ziarnisty
obciążenie wybuchowe
metoda elementów dyskretnych
granular medium
blast load
discrete element method
Opis:
W pracy przedstawiono analizę numeryczną skuteczności redukcji ciśnienia wybuchu przekazywanego na strop obiektu poprzez zastosowanie warstwy tłumiącej z materiału ziarnistego, na której umieszczono płytę ochronną. Analizy przeprowadzono metodą elementów dyskretnych, podano zmienności w czasie naprężeń stanowiących obciążenie stropu przy zadanym impulsie nadciśnienia wybuchowego. Wykazano, że masa płyty ochronnej wpływa istotnie na rozkład nadciśnienia przekazywanego na strop. Uzyskane rozwiązania numeryczne wskazują na ujęcie efektów kilkukrotnych odbić fali ciśnienia w ośrodku ziarnistym ograniczonym sztywnymi przegrodami — płyty ochronnej i stropu.
The paper presents numerical analysis of effectiveness of reduction of blast load pressure acting on the ceiling by using granular medium with a cover plate. The analysis was conducted using the discrete element method. The variability of stress acting on the ceiling under blast load impulse is presented. It is shown that plate weight significantly influences on the character of ceiling pressure distribution. The obtained numerical results reveal multiple stress wave reflection effects in granular medium placed between the rigid cover plate and the ceiling.
Źródło:
Biuletyn Wojskowej Akademii Technicznej; 2016, 65, 3; 159-167
1234-5865
Pojawia się w:
Biuletyn Wojskowej Akademii Technicznej
Dostawca treści:
Biblioteka Nauki
Artykuł
Wyświetlanie 1-25 z 60

Ta witryna wykorzystuje pliki cookies do przechowywania informacji na Twoim komputerze. Pliki cookies stosujemy w celu świadczenia usług na najwyższym poziomie, w tym w sposób dostosowany do indywidualnych potrzeb. Korzystanie z witryny bez zmiany ustawień dotyczących cookies oznacza, że będą one zamieszczane w Twoim komputerze. W każdym momencie możesz dokonać zmiany ustawień dotyczących cookies