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Wyszukujesz frazę "continuous modelling" wg kryterium: Temat


Tytuł:
Implementation of Distributed Hydrological Modeling in a Semi-Arid Mediterranean Catchment Azzaba, Morocco
Autorzy:
Abdelmounim, Bouadila
Benaabidate, Lahcen
Bouizrou, Ismail
Aqnouy, Mourad
Powiązania:
https://bibliotekanauki.pl/articles/123743.pdf
Data publikacji:
2019
Wydawca:
Polskie Towarzystwo Inżynierii Ekologicznej
Tematy:
semi-arid mediterranean context
flood forecasting
continuous modelling
event-based modelling
ATHYS platform
distributed SCS-LR model
Opis:
The typical Mediterranean climate is marked at certain times of the year by sudden torrential rains causing high water flows, which leads to heavy flooding and hydroclimatic fluctuations due to a semi-arid climate. This explains the need for hydrological modeling for water resource management in these contexts. This work concerns the hydrological modeling of the Azzaba catchment area in Haut-Sebou “Morocco”. In the first part of this work, a bibliographic synthesis was carried out to characterize certain factors (physical, geological and climatic), and a hydrological study was carried out by processing rainfall and hydrometric data from the considered time periods. Ultimately, the use of the “ATHYS” platform is beginning to reproduce the flows at the Azzaba outlet. This model is really applicable in the semi-arid context based on several studies carried out on these contexts, since it has to consider the chronological sequence of phenomena on one hand and the influence of the climatic and physicalhydrogeological parameters of the basin (humidity and soil exchange) on the other. Several criteria were used in this study to estimate the model performance; the most common is Nash-Sutcliffe. After observation and analysis of the overall results, it can be concluded that the model reproduces flows in the Azzaba River watershed well, especially in event mode (mean Nash-Sutcliffe value of 0.71). The use of a historical meteorological time series to simulate flow using a daily time step gives average results with a Nash of 0.50, which strengthens the reliability of the ATHYS platform in the Mediterranean climate area.
Źródło:
Journal of Ecological Engineering; 2019, 20, 6; 236-254
2299-8993
Pojawia się w:
Journal of Ecological Engineering
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
Optimization of Steel Flow in the Tundish by Modifying its Working Area
Autorzy:
Warzecha, P.
Hutny, A. M.
Warzecha, M.
Merder, T.
Powiązania:
https://bibliotekanauki.pl/articles/354772.pdf
Data publikacji:
2016
Wydawca:
Polska Akademia Nauk. Czytelnia Czasopism PAN
Tematy:
tundish
continuous casting
numerical modelling
Opis:
Presented paper describes model investigations carried out on six-strand continuous casting tundish. Numerical analysis is based on simulations performed with the use of commercial code ANSYS Fluent. The analysis concerns determination of hydrodynamic conditions of the flow in the analysed tundish, with nominal capacity of 22 Mg, and its optimisation by modification of the flow structure in the tundish working area. Four different flow control devices (FCD) were proposed. Results of investigations presented in the paper include the distribution of velocity vectors and distribution of temperature and turbulence kinetic energy. Additionally, for more detailed comparative analysis, the macroscopic characteristics of residence time distribution (RTD) in the reactor, and the transition zone ranges were determined for each of the variants.
Źródło:
Archives of Metallurgy and Materials; 2016, 61, 4; 2071-2078
1733-3490
Pojawia się w:
Archives of Metallurgy and Materials
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
Numerical Analysis of the Structure of Liquid Flow in the Tundish with Physical Model Verification
Autorzy:
Merder, T.
Powiązania:
https://bibliotekanauki.pl/articles/352430.pdf
Data publikacji:
2018
Wydawca:
Polska Akademia Nauk. Czytelnia Czasopism PAN
Tematy:
steelmaking
continuous casting
tundish
numerical modelling
physical modelling
Opis:
Detailed studies of the movement of liquid steel (hydrodynamics) on a real object are practically impossible. The solution to this problem are physical modelling carried out on water models and numerical modelling using appropriate programs. The method of numerical modelling thanks to the considerable computing power of modern computers gives the possibility of solving very complex problems. The paper presents the results of model tests of liquid flow through tundish. The examined object was model of the twonozzle tundish model. The ANSYS Fluent program was used to describe the behavior of liquid in the working area of the tundish model. Numerical simulations were carried out using two numerical methods of turbulence description: RANS (Reynolds-Averaged Navier-Stokes) – model k-ε and LES (Large Eddy Simulation). The results obtained from CFD calculations were compared with the results obtained using the water model.
Źródło:
Archives of Metallurgy and Materials; 2018, 63, 4; 1895-1901
1733-3490
Pojawia się w:
Archives of Metallurgy and Materials
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
Hydrodynamic conditions of flow in the tundish depending on selected technological parameters for different steel groups
Autorzy:
Warzecha, M.
Merder, T.
Warzecha, P.
Hutny, A. M.
Powiązania:
https://bibliotekanauki.pl/articles/353743.pdf
Data publikacji:
2019
Wydawca:
Polska Akademia Nauk. Czytelnia Czasopism PAN
Tematy:
steelmaking
continuous casting
tundish
numerical modelling
Opis:
The presented results of investigations are part of a larger study focused on the optimization of the flow and mixing of liquid steel in the industrial tundish of continuous casting machine. The numerical simulations were carried out concern the analysis of hydrodynamic conditions of liquid steel flow in a tundish operating in one of the national steelworks. Numerical simulations were performed using the commercial code ANSYS Fluent. The research concerns two different speeds of steel casting. In real conditions, these speeds are the most commonly used in the technological process when casting two different groups of steel. As a result of computational fluid dynamics (CFD) calculations, predicted spatial distributions of velocity and liquid steel turbulence fields and residence time distribution (RTD) curves were obtained. The volume fractions of different flows occurring in the tundish were also calculated. The results of the research allowed a detailed analysis of the influence of casting speed on the formation of hydrodynamic conditions prevailing in the reactor.
Źródło:
Archives of Metallurgy and Materials; 2019, 64, 1; 65-70
1733-3490
Pojawia się w:
Archives of Metallurgy and Materials
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
Experimental Methods of Validation for Numerical Simulation Results on Steel Flow through Tundish
Autorzy:
Pieprzyca, J.
Warzecha, P.
Merder, T.
Warzecha, M.
Powiązania:
https://bibliotekanauki.pl/articles/355968.pdf
Data publikacji:
2016
Wydawca:
Polska Akademia Nauk. Czytelnia Czasopism PAN
Tematy:
continuous casting
tundish
physical modelling
numerical modeling
Opis:
The article presents experimental results on the impact of tundish flow regulator influencing the liquid steel flow course. The research was conducted based on the hybrid modelling methods understood as a complementary use of Computational Fluid Dynamics (CFD) methods and physical modelling. Dynamic development of numerical simulation techniques and accessibility to highly advanced and specialized software causes the fact that these techniques are commonly used for solving problems related to liquid flows by using analytical methods. Whereas, physical modelling is an important cognitive tool in the field of empirical identification of these phenomena. This allows for peer review and specification of the researched problems. By exploiting these relationships, a comparison of the obtained results was performed in the form of residence time distribution (RTD) curves and visualization of particular types of liquid steel flow distribution zones in the investigated tundish.
Źródło:
Archives of Metallurgy and Materials; 2016, 61, 4; 2057-2060
1733-3490
Pojawia się w:
Archives of Metallurgy and Materials
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
Study of Solidification of Continuously Cast Steel Round Billets Using Numerical Modellin
Autorzy:
Tkadleckova, M.
Válek, L.
Socha, L.
Saternus, M.
Pieprzyca, J.
Merder, T.
Michalek, K.
Kováč, M.
Powiązania:
https://bibliotekanauki.pl/articles/353911.pdf
Data publikacji:
2016
Wydawca:
Polska Akademia Nauk. Czytelnia Czasopism PAN
Tematy:
steel
billet
continuous casting
numerical modelling
metallurgical length
Opis:
The paper is dedicated to the verification of solidification of continuously cast round steel billets using numerical modelling based on the finite element method. The aim of numerical modelling is to optimize the production of continuously cast steel billets of round format. The paper describes the pre-processing, processing and post-processing phases of numerical modelling. Also, the problems with determination of the thermodynamic properties of materials and the heat transfer between the individual parts of the casting system, including the definition of the heat losses along the casting strand in the primary and secondary cooling, were discussed. The first results of numerical simulation show the so-called thermal steady state of continuous casting. The temperature field, the metallurgical length and the thickness of the shell at the end of the mould were predicted. The further research will be concentrated on the prediction the risk of the cracks and the porosity based on the different boundary conditions.
Źródło:
Archives of Metallurgy and Materials; 2016, 61, 1; 221-226
1733-3490
Pojawia się w:
Archives of Metallurgy and Materials
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
The Effect of Thermophysical Parameters on Temperature Distribution in the Primary Cooling Zone
Autorzy:
Miłkowska-Piszczek, K.
Powiązania:
https://bibliotekanauki.pl/articles/958194.pdf
Data publikacji:
2016
Wydawca:
Polska Akademia Nauk. Czytelnia Czasopism PAN
Tematy:
continuous casting of steel
enthalpy
numerical modelling
ProCAST
Opis:
The values of thermophysical properties obtained from the experimental research, and those that were calculated with thermodynamic databases, are crucial parameters which were used in the numerical modelling of the steel solidification process. This paper presents the results of research on the impact of specific heat and enthalpy, along with the method of their implementation, on temperature distribution in the primary cooling zone in the continuous steel casting process. A cast slab – with dimensions of 1100 mm and 220 mm and a S235 steel grade – was analysed. A mould with a submerged entry nozzle (SEN), based on the actual dimensions of the slab continuous casting machine, was implemented. The research problem was solved with the finite element method using the ProCAST software package. Simulations were conducted using the “THERMAL + FLOW” module.
Źródło:
Archives of Metallurgy and Materials; 2016, 61, 4; 2079-2082
1733-3490
Pojawia się w:
Archives of Metallurgy and Materials
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
Strategy of Cooling Parameters Selection in the Continuous Casting of Steel
Autorzy:
Falkus, J.
Miłkowska-Piszczek, K.
Powiązania:
https://bibliotekanauki.pl/articles/352539.pdf
Data publikacji:
2016
Wydawca:
Polska Akademia Nauk. Czytelnia Czasopism PAN
Tematy:
continuous casting of steel
cooling parameters
numerical modelling
Opis:
This paper presents a strategy of the cooling parameters selection in the process of continuous steel casting. Industrial tests were performed at a slab casting machine at the Arcelor Mittal Poland Unit in Krakow. The tests covered 55 heats for 7 various steel grades. Based on the existing casting technology a numerical model of the continuous steel casting process was formulated. The numerical calculations were performed for three casting speeds - 0.6, 0.8 and 1 m min-1. An algorithm was presented that allows us to compute the values of the heat transfer coefficients for the secondary cooling zone. The correctness of the cooling parameter strategy was evaluated by inspecting the shell thickness, the length of the liquid core and the strand surface temperature. The ProCAST software package was used to construct the numerical model of continuous casting of steel.
Źródło:
Archives of Metallurgy and Materials; 2016, 61, 1; 329-334
1733-3490
Pojawia się w:
Archives of Metallurgy and Materials
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
Innovative educational program for biogas production carried out at University of Hradec Králové (CZ) and at University of Opole (PL)
Innowacyjny program edukacyjny dotyczący wytwarzania biogazu realizowany na uniwersytetach w Hradec Králové (CZ) i Opolu (PL)
Autorzy:
Loskot, J.
Smolík, M.
Hyšplerová, L.
Radocha, K.
Kříž, J.
Eminger, S.
Dołhańczuk-Śródka, A.
Ziembik, Z.
Wacławek, M.
Powiązania:
https://bibliotekanauki.pl/articles/106474.pdf
Data publikacji:
2016
Wydawca:
Towarzystwo Chemii i Inżynierii Ekologicznej
Tematy:
biogas plants
continuous measurement
modelling
biogazownie
pomiar ciągły
modelowanie
Opis:
Recently, there is a growing pressure on a rapid construction of agricultural biogas plants, particularly in the Czech-Polish border region. It is an area with large expanses of agricultural land which can serve to supply biogas plants with biomass. This strategy should contribute to harmonize the common agricultural policy of the European Union. A need for qualified operators of these stations on this territory is also increasing. Therefore we first include a demonstration of an education program for students in the field of agricultural waste anaerobic fermentation and biogas production. We present here the first part of an innovative approach which we use in the teaching program “Physico-technical Measurements and Computer Technology” at the Faculty of Science at the University of Hradec Kralove and also in the education of internshipers from the Faculty of Natural Sciences and Technology at the University of Opole. There are requirements to fulfil labour market expectations and to make this subject more attractive for the students. Students’ theoretical and practical preparation constitutes a comprehensive source of knowledge and skills required in a real life job. Joined theoretical and practical knowledge gained by students, reinforced by the skills developed during task analysis followed by their solution, provides the future graduate higher quality abilities and better position in the labour market.
W ostatnim czasie rośnie nacisk na budowę biogazowni rolniczych, szczególnie w czesko-polskim regionie przygranicznym. Jest to region, gdzie występują duże obszary gruntów rolnych mogących służyć do zasilania biogazowni. Strategia ta powinna przyczynić się do harmonizacji wspólnej polityki rolnej Unii Europejskiej. W związku z powyższym wzrasta również potrzeba wykształcenia wykwalifikowanych operatorów tych stacji. Pierwsza część pracy obejmuje prezentację akademickiego programu edukacyjnego w dziedzinie fermentacji beztlenowej odpadów i wytwarzania biogazu pochodzącego z produkcji rolnej. Zaprezentowano część innowacyjnego podejścia, które wykorzystywane jest w programie nauczania „Pomiary fizyko-techniczne oraz technologie komputerowe” na Wydziale Nauk Przyrodniczych Uniwersytetu Hradec Kralove, a także w edukacji studentów Wydziału Przyrodniczo-Technicznego Uniwersytetu Opolskiego. Wymagania te mają sprostać oczekiwaniom rynku pracy i uczynić kierunek studiów bardziej atrakcyjnym. Powiązanie przygotowania teoretycznego i praktycznego studentów tworzy kompleksowe źródło wiedzy i kształtuje umiejętności niezbędnych do pracy w biogazowniach. Zarówno wiedza teoretyczna, jak i umiejętności praktyczne zdobyte przez studentów, wzbogacone o umiejętności analizy zadań, a następnie ich rozwiązania, zapewnią przyszłym absolwentom większe możliwości i lepszą pozycję na rynku pracy.
Źródło:
Chemistry-Didactics-Ecology-Metrology; 2016, 21, 1-2; 61-74
2084-4506
Pojawia się w:
Chemistry-Didactics-Ecology-Metrology
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
Evaluation of Approaches of Numerical Modelling of Solidification of Continuously Cast Steel Billets
Autorzy:
Tkadlečková, M.
Michalek, K.
Strouhalová, M.
Sviželová, J.
Saternus, M.
Pieprzyca, J.
Merder, T.
Powiązania:
https://bibliotekanauki.pl/articles/354682.pdf
Data publikacji:
2018
Wydawca:
Polska Akademia Nauk. Czytelnia Czasopism PAN
Tematy:
steel
steelmaking
continuous casting
numerical modelling
temperature field
porosity
Opis:
The paper evaluates two approaches of numerical modelling of solidification of continuously cast steel billets by finite element method, namely by the numerical modelling under the Steady-State Thermal Conditions, and by the numerical modelling with the Traveling Boundary Conditions. In the paper, the 3D drawing of the geometry, the preparation of computational mesh, the definition of boundary conditions and also the definition of thermo-physical properties of materials in relation to the expected results are discussed. The effect of thermo-physical properties on the computation of central porosity in billet is also mentioned. In conclusion, the advantages and disadvantages of two described approaches are listed and the direction of the next research in the prediction of temperature field in continuously cast billets is also outlined.
Źródło:
Archives of Metallurgy and Materials; 2018, 63, 2; 1003-1008
1733-3490
Pojawia się w:
Archives of Metallurgy and Materials
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
The Change of Liquid Steel Flow Control System in the Tundish – Modelling Research
Zmiana systemu kontroli przepływu ciekłej stali w kadzi pośredniej – badania modelowe
Autorzy:
Pieprzyca, J.
Merder, T.
Saternus, M.
Kania, H.
Powiązania:
https://bibliotekanauki.pl/articles/354425.pdf
Data publikacji:
2014
Wydawca:
Polska Akademia Nauk. Czytelnia Czasopism PAN
Tematy:
tundish
continuous casting
physical modelling
numerical modelling
kadź pośrednia
odlewanie ciągłe
modelowanie fizyczne
modelowanie numeryczne
Opis:
The article presents the results of research concerning the change of liquid steel flow and mixing in the T-type tundish. It has been installed in one of polish steel plants. Continuously changing market conditions have forced the change in the range of cast strand. As a consequence the new control system of liquid steel flow had to be applied. Up to now a baffle with notch has played the role of steel flow regulation. It was placed between the inlet and channel zones of a tundish. However such solution was not satisfactory. Therefore, a new flow control equipment was designed - baffles and different constructional variants of turbulence inhibitors. To estimate the efficiency of their functioning and in the same time their influence on the tundish work, modelling research was carried out. The research was also complemented by numerical simulations. The article presents results of such research as well as experimentally and numerically determined RTD curves of mixing (Residence Time Distribution).
Artykuł przedstawia rezultaty badań dotyczące zmiany przepływu i mieszania się ciekłej stali w kadzi pośredniej typu T. Urządzenie to zainstalowane jest w jednej z polskich stalowni. Zmieniające się warunki rynkowe wymusiły zmianę asortymentu odlewanych wlewków ciągłych, a tym samym wymusiły konieczność zastosowania w kadzi pośredniej nowego systemu regulacji przepływu stali. Dotychczasową zabudowę stanowiła przegroda z otworem przelewowym. Przegroda umieszczona była pomiędzy strefa wlewowa i korytowa kadzi pośredniej. To rozwiązanie nie spełniało oczekiwan. W związku z tym zaprojektowano nowe urządzenia sterowania przepływem, takie jak: przegrody i różne warianty konstrukcyjne inhibitora turbulencji. W celu oceny zaprojektowanych urządzeń sterowania przepływem i ich wpływu na prace kadzi pośredniej przeprowadzono badania na modelu fizycznym uzupełniając je o symulacje numeryczne. Artykuł prezentuje wyniki badań modelowych wizualizacji przepływu uzupełnione o krzywe mieszania RTD (Residence Time Distribution).
Źródło:
Archives of Metallurgy and Materials; 2014, 59, 4; 1433-1440
1733-3490
Pojawia się w:
Archives of Metallurgy and Materials
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
Co możemy opisać układem dynamicznym?
What can we describe by dynamical systems?
Autorzy:
Foryś, Urszula
Powiązania:
https://bibliotekanauki.pl/articles/1790992.pdf
Data publikacji:
2017-07-05
Wydawca:
Uniwersytet Pedagogiczny im. Komisji Edukacji Narodowej w Krakowie
Tematy:
dynamical system
mathematical modelling
discrete model
continuous
model
stability
eigenvalue
Opis:
In this paper we present several examples of simple dynamical systemsdescribing various real processes. We start from well know Fibonaccisequence, through Lotka-Volterra model of prey-predator system, love affairdynamics, ending with modelling of tumour growth.
Źródło:
Annales Universitatis Paedagogicae Cracoviensis. Studia ad Didacticam Mathematicae Pertinentia; 2014, 6; 73-85
2080-9751
2450-341X
Pojawia się w:
Annales Universitatis Paedagogicae Cracoviensis. Studia ad Didacticam Mathematicae Pertinentia
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
Computer Simulation of the Formation of Non-Metallic Precipitates During a Continuous Casting of Steel
Autorzy:
Kalisz, D.
Żak, P. L.
Tokarski, T.
Wzorek, Ł.
Suchy, J. S.
Kiczor, M.
Cieślak, W.
Powiązania:
https://bibliotekanauki.pl/articles/958226.pdf
Data publikacji:
2016
Wydawca:
Polska Akademia Nauk. Czytelnia Czasopism PAN
Tematy:
non-metallic oxide precipitates
modelling
continuous casting of steel
crystallization
Opis:
The authors own computer software, based on the Ueshima mathematical model with taking into account the back diffusion, determined from the Wołczyński equation, was developed for simulation calculations. The applied calculation procedure allowed to determine the chemical composition of the non-metallic phase in steel deoxidised by means of Mn, Si and Al, at the given cooling rate. The calculation results were confirmed by the analysis of samples taken from the determined areas of the cast ingot. This indicates that the developed computer software can be applied for designing the steel casting process of the strictly determined chemical composition and for obtaining the required non-metallic precipitates.
Źródło:
Archives of Metallurgy and Materials; 2016, 61, 1; 335-340
1733-3490
Pojawia się w:
Archives of Metallurgy and Materials
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
On the mathematical condition-based maintenance modelling for continuously deteriorating systems
Autorzy:
Bérenguer, C.
Powiązania:
https://bibliotekanauki.pl/articles/2069561.pdf
Data publikacji:
2008
Wydawca:
Uniwersytet Morski w Gdyni. Polskie Towarzystwo Bezpieczeństwa i Niezawodności
Tematy:
condition-based maintenance
continuous deterioration
stochastic modelling
Gamma process
semi-regeneration
Opis:
This paper presents a modelling framework of condition-based maintenance policies for continuously deteriorating systems, based on semi-regenerative stochastic techniques.
Źródło:
Journal of Polish Safety and Reliability Association; 2008, 1; 41--52
2084-5316
Pojawia się w:
Journal of Polish Safety and Reliability Association
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
An improvement of Gamma approximation for reduction of continuous interval systems
Autorzy:
Bokam, Jagadish Kumar
Singh, Vinay Pratap
Devarapalli, Ramesh
García Márquez, Fausto Pedro
Powiązania:
https://bibliotekanauki.pl/articles/1409387.pdf
Data publikacji:
2021
Wydawca:
Polska Akademia Nauk. Czytelnia Czasopism PAN
Tematy:
continuous interval systems
Kharitonov polynomials
Routh approximation
modelling
SISO systems
MIMO systems
Opis:
In recent, modeling practical systems as interval systems is gaining more attention of control researchers due to various advantages of interval systems. This research work presents a new approach for reducing the high-order continuous interval system (HOCIS) utilizing improved Gamma approximation. The denominator polynomial of reduced-order continuous interval model (ROCIM) is obtained using modified Routh table, while the numerator polynomial is derived using Gamma parameters. The distinctive features of this approach are: (i) It always generates a stable model for stable HOCIS in contrast to other recent existing techniques; (ii) It always produces interval models for interval systems in contrast to other relevant methods, and, (iii) The proposed technique can be applied to any system in opposite to some existing techniques which are applicable to second-order and third-order systems only. The accuracy and effectiveness of the proposed method are demonstrated by considering test cases of single-inputsingle-output (SISO) and multi-input-multi-output (MIMO) continuous interval systems. The robust stability analysis for ROCIM is also presented to support the effectiveness of proposed technique.
Źródło:
Archives of Control Sciences; 2021, 31, 2; 347-373
1230-2384
Pojawia się w:
Archives of Control Sciences
Dostawca treści:
Biblioteka Nauki
Artykuł

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