Informacja

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

Wyszukujesz frazę "steady state" wg kryterium: Temat


Tytuł:
Stator current spectrum analysis of a double cage induction motor with rotor asymmetry
Autorzy:
Tulicki, Jarosław
Sobczyk, Tadeusz Jan
Sułowicz, Maciej
Powiązania:
https://bibliotekanauki.pl/articles/24202742.pdf
Data publikacji:
2023
Wydawca:
Polska Akademia Nauk. Czasopisma i Monografie PAN
Tematy:
cage asymmetry
double cage induction motor
harmonic balance method
steady-state analysis
stator current Fourier spectra
Opis:
This study presents a method to directly calculate the stator current Fourier spectra in double-cage induction motors to diagnose faults in rotor cages. A circuit model is developed for this purpose, allowing the modelling of any asymmetry in the outer and inner rotor cages. The model extends the conventional model of a cage motor by considering the higher space harmonics generated by the stator windings. The asymmetry of the cages is modelled by growing the resistance of any of the rotor bars. This results in various model equations, to be solved by looking for diagnostic signals. Motor current signature analysis is typically used to diagnose cage motors based on the Fourier spectra of the stator currents during steady-state operation. This study determines these spectra for double cage motors using the harmonic balance method, omitting the transient calculations. The calculation results confirmed the sensitivity of the stator current Fourier spectra as a diagnostic signal to distinguish faults in the outer and inner cages.
Źródło:
Archives of Electrical Engineering; 2023, 72, 2; 357--371
1427-4221
2300-2506
Pojawia się w:
Archives of Electrical Engineering
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
A discussion on the optimality of bulk entry queue with differentiated hiatuses
Autorzy:
Vadivukarasi, Manickam
Kalidass, Kaliappan
Powiązania:
https://bibliotekanauki.pl/articles/2175843.pdf
Data publikacji:
2022
Wydawca:
Politechnika Wrocławska. Oficyna Wydawnicza Politechniki Wrocławskiej
Tematy:
differentiated hiatus time
steady state probability
waiting-time distribution
optimization of expenses
Opis:
We consider Markovian differentiated hiatuses queues with bulk entries. With the help of the matrix geometric method, we discuss the stability condition for the existence of the steady-state solution of our model and we obtain the stationary system size by using a probability generating function. The stochastic decomposition form of stationary system size and the waiting time distribution of an arbitrary beneficiary are also analysed. Furthermore, we perform the expense analysis using the particle swarm optimization technique and we obtain the optimality of service rate and hiatus rate. Finally, we study the effects of changes in the parameters on some important performance measures of the system through numerical observations.
Źródło:
Operations Research and Decisions; 2022, 32, 2; 137--150
2081-8858
2391-6060
Pojawia się w:
Operations Research and Decisions
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
Numerical analysis of an auxetic anti-tetrachiral sandwich panel subjected to steady-state harmonic base motion
Autorzy:
Michalski, Jakub
Stręk, Tomasz
Powiązania:
https://bibliotekanauki.pl/articles/24202005.pdf
Data publikacji:
2022
Wydawca:
Politechnika Poznańska. Instytut Mechaniki Stosowanej
Tematy:
steady state dynamics
auxetic
sandwich panel
base motion
finite element analysis
dynamika stanu ustalonego
auksetyk
płyta warstwowa
analiza elementów skończonych
Opis:
In this paper, the authors show the results of numerical simulations representing the test of an aluminum sandwich panel with an auxetic anti-tetrachiral core on an exciter. Steady-state vibration analyses utilizing modal superposition (linear dynamics) were performed. The bottom of the panel had all the degrees of freedom constrained and excitation in form of base acceleration in the vertical direction was applied. The obtained results were in form of contour plots of selected output variables in the frequency domain. In addition, curves showing the variation of acceleration, velocity and displacement of a selected representative point in frequency were generated. The results were compared with those obtained for the panel with a non-auxetic core, in the form of a standard hexagonal honeycomb. It was found that the auxetic panel is not superior in the whole range of frequencies but a workflow useful in the design of sandwich panels for operating conditions involving vibrations was developed.
Źródło:
Vibrations in Physical Systems; 2022, 33, 3; art. no. 2022323
0860-6897
Pojawia się w:
Vibrations in Physical Systems
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
Use of Synthesis Gas as Fuel for a Solid Oxide Fuel Cell
Autorzy:
Alvarez-Cedillo, Jesus A.
Alvarez-Sanchez, Teodoro
Sandoval-Gomez, Raul J.
Gonzalez-Vasquez, Alexis
Sarabia-Alonso, Teresa
Powiązania:
https://bibliotekanauki.pl/articles/2202146.pdf
Data publikacji:
2022
Wydawca:
Polskie Towarzystwo Inżynierii Ekologicznej
Tematy:
anode
cathode
electrolyte
biomass
syngas
solid oxide fuel cell
mathematical model
steady state
Opis:
There is a real need to use various efficient energy supply systems that are not aggressive towards the global environment. Hydrogen has been seen in different research papers presented in the literature as an essential fuel to generate energy in various energy storage systems. As it is well-known, it is possible to generate renewable electricity using electrolysis. The hydrogen produced can be sold as fuel for various systems, most notably its use in solid oxide fuel cells and a host of modern applications today. Current low-temperature fuel cells are ideal for hydrogen operation, but are not suitable for hydrogen mixtures. In this article, a mathematical analysis was carried out to generate electrical energy in a fuel cell, fed with synthesis gas from the residual biomass gasification process; the primary interest was the generation of electrical energy, solid oxide fuel cell (SOFC), which operate at the temperature of the gas at the outlet of the gasifier were analyzed. The practical efficiency obtained and the theoretical results of the SOFC operation were shown.
Źródło:
Journal of Ecological Engineering; 2022, 23, 10; 35--41
2299-8993
Pojawia się w:
Journal of Ecological Engineering
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
Hot Deformation Activation Energy of Metallic Materials Influenced by Strain Value
Autorzy:
Schindler, I.
Opěla, P.
Kawulok, P.
Sauer, M.
Rusz, S.
Kuc, D.
Rodak, K.
Powiązania:
https://bibliotekanauki.pl/articles/2049432.pdf
Data publikacji:
2021
Wydawca:
Polska Akademia Nauk. Czytelnia Czasopism PAN
Tematy:
flow stress curves
steady state
metallic materials
hot deformation activation energy
Opis:
Suitable and complete sets of stress-strain curves significantly affected by dynamic recrystallization were analyzed for 11 different iron, copper, magnesium, titanium or nickel based alloys. Using the same methodology, apparent hot deformation activation energy Qp and Qss values were calculated for each alloy based on peak stress and steady-state stress values. Linear dependence between quantities Qp and Qss was found, while Qp values are on average only about 6% higher. This should not be essential in predicting true stress of a specific material depending on the temperature-compensated strain rate and strain.
Źródło:
Archives of Metallurgy and Materials; 2021, 66, 1; 223-228
1733-3490
Pojawia się w:
Archives of Metallurgy and Materials
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
Modified integer model for solving the master bay problem
Autorzy:
Tsymbal, M.
Kamieniev, K.
Powiązania:
https://bibliotekanauki.pl/articles/2063952.pdf
Data publikacji:
2021
Wydawca:
Uniwersytet Morski w Gdyni. Wydział Nawigacyjny
Tematy:
ship operation problem
master bay problem
integer model
modified integer model
genetic algorithm
steady-state genetic algorithm
numerical experiment
feasibility study
Opis:
One of key components in keeping a ship seaworthy is a correctly prepared cargo plan. Considering the recent cost cutting measures and reduced transportation volumes relevance of optimizing such a plan cannot be understated. Though there’s a number of studies addressing the issue none of them covers all the operational and constructional constraints necessary to factor for. This article presents an integer model that tries to address some of the constraints missed by other researches. A method for solving the model is designed and developed based on a steady-state genetic algorithm. A numerical experiment is conducted showing the method’s feasibility.
Źródło:
TransNav : International Journal on Marine Navigation and Safety of Sea Transportation; 2021, 15, 3; 749--753
2083-6473
2083-6481
Pojawia się w:
TransNav : International Journal on Marine Navigation and Safety of Sea Transportation
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
Determination of Hopf bifurcation sets of a chemicalreactors by two-parameter continuation method
Autorzy:
Berezowski, Marek
Powiązania:
https://bibliotekanauki.pl/articles/185121.pdf
Data publikacji:
2020
Wydawca:
Polska Akademia Nauk. Czytelnia Czasopism PAN
Tematy:
chemical reactor
Hopf bifurcation
thank reactor
bifurcation diagram
steady state
stability
dynamics
reaktor chemiczny
Rozwidlenie Hopfa
diagram bifurkacji
stan stabilny
stabilność
dynamika
Opis:
A two-parameter continuation method was developed and shown in the form of an example, allowingdetermination of Hopf bifurcation sets in a chemical reactor model. Exemplary calculations weremade for the continuous stirred tank reactor model (CSTR). The set of HB points limiting the rangeof oscillation in the reactor was determined. The results were confirmed on the bifurcation diagramof steady states and on time charts. The method is universal and can be used for various models ofchemical reactors.
Źródło:
Chemical and Process Engineering; 2020, 41, 3; 221--227
0208-6425
2300-1925
Pojawia się w:
Chemical and Process Engineering
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
Rationalization of the energy consumption of road transport for sustainable development
Autorzy:
Szaruga, Elżbieta
Powiązania:
https://bibliotekanauki.pl/articles/135696.pdf
Data publikacji:
2020
Wydawca:
Akademia Morska w Szczecinie. Wydawnictwo AMSz
Tematy:
energy consumption
freight road transport
rationalization
steady-state economy
sustainable development
vector error correction model
Opis:
This paper presents an approach to rationalize the energy consumption of road transport towards sustainability in a steady-state economy. The research hypothesis is that the rationalization of the energy consumption of road transport is affected by drift and shocks, which desynchronizes the adjustment mechanism from equilibrium. The objective of this research was to incorporate the model of energy consumption of road freight transport with the goals of sustainability by considering ecological and constructivist rational orders, the issue of order drift, and the occurrence of shocks. The research investigated Poland from the first quarter of 2004 to the fourth quarter of 2018. A model for rationalizing the energy consumption of road transport was constructed using the vector error correction model and cointegration techniques. The model revealed one cointegrating relationship and showed statistically significant unlimited drift. The level of changes to long-term equilibrium appeared respectively for GDP – 1.8%, PPI for energy – 7.3%, and for energy consumption – 10.9%. We observed a weak sustainability between the energy consumption of road transport and GDP and a strong sustainability between energy consumption of road transport and PPI energy. It was determined that price shocks had a positive impact (at the estimated point level around 0.06) and supply and demand shocks had a negative impact (at the level estimated point around –3).
Źródło:
Zeszyty Naukowe Akademii Morskiej w Szczecinie; 2020, 62 (134); 36-42
1733-8670
2392-0378
Pojawia się w:
Zeszyty Naukowe Akademii Morskiej w Szczecinie
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
ZA-APA with Adaptive Zero Attractor Controller for Variable Sparsity Environment
Autorzy:
Radhika, S.
Chandrasekar, A.
Nirmalraj, S.
Powiązania:
https://bibliotekanauki.pl/articles/1844469.pdf
Data publikacji:
2020
Wydawca:
Polska Akademia Nauk. Czytelnia Czasopism PAN
Tematy:
Zero Attraction APA
sparse channel
convergence
steady state mean square error
variable zero attraction controller
Opis:
The zero attraction affine projection algorithm (ZA-APA) achieves better performance in terms of convergence rate and steady state error than standard APA when the system is sparse. It uses l1 norm penalty to exploit sparsity of the channel. The performance of ZA-APA depends on the value of zero attractor controller. Moreover a fixed attractor controller is not suitable for varying sparsity environment. This paper proposes an optimal adaptive zero attractor controller based on Mean Square Deviation (MSD) error to work in variable sparsity environment. Experiments were conducted to prove the suitability of the proposed algorithm for identification of unknown variable sparse system.
Źródło:
International Journal of Electronics and Telecommunications; 2020, 66, 4; 695-700
2300-1933
Pojawia się w:
International Journal of Electronics and Telecommunications
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
Application of the ASTM D5470 standard test method for thermal conductivity measurements of high thermal conductive materials
Autorzy:
Buliński, Z.
Pawlak, S.
Krysiński, T.
Adamczyk, W.
Białecki, R.
Powiązania:
https://bibliotekanauki.pl/articles/367975.pdf
Data publikacji:
2019
Wydawca:
Stowarzyszenie Komputerowej Nauki o Materiałach i Inżynierii Powierzchni w Gliwicach
Tematy:
thermal conductivity
thermal resistance
steady-state heat transfer
ASTM D5470 standard
przewodność cieplna
opór cieplny
ustalony przepływ ciepła
Opis:
Purpose: The purpose of the present study was to demonstrate the procedure for determining the thermal conductivity of a solid material with relatively high thermal conductivity, using an original self-designed apparatus. Design/methodology/approach: The thermal conductivity measurements have been performed according to the ASTM D5470 standard. The thermal conductivity was calculated from the recorded temperature values in steady-state heat transfer conditions and determined heat flux. Findings: It has been found from the obtained experimental results that the applied standard test method, which was initially introduced for thermal conductivity measurements of thermal interface materials (TIMs), is also suitable for materials with high thermal conductivity, giving reliable results. Research limitations/implications: The ASTM D5470 standard test method for measurement of thermal conductivity usually gives poor results for high conductive materials having thermal conductivity above 100 W/mK, due to problems with measuring heat flux and temperature drop across the investigated sample with reasonably high accuracy. Practical implications: The results obtained for the tested material show that the presented standard test method can also be used for materials with high thermal conductivity, which is of importance either for the industrial or laboratory applications. Originality/value: The thermal conductivity measurements have been carried out using an original self-designed apparatus, which was developed for testing broad range of engineering materials with high accuracy.
Źródło:
Journal of Achievements in Materials and Manufacturing Engineering; 2019, 95, 2; 57-63
1734-8412
Pojawia się w:
Journal of Achievements in Materials and Manufacturing Engineering
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
Heat conduction in anisotropic medium with perfectly conductive thread-like inclusions
Autorzy:
Sulym, Heorhiy
Ilchuk, Nataliia
Pasternak, Iaroslav
Powiązania:
https://bibliotekanauki.pl/articles/387323.pdf
Data publikacji:
2019
Wydawca:
Politechnika Białostocka. Oficyna Wydawnicza Politechniki Białostockiej
Tematy:
thread-like inclusion
steady-state heat conduction
anisotropy
boundary integral equation
hypersingular
Opis:
The paper presents a novel approach for the analysis of steady-state heat conduction of solids containing perfectly conductive thread-like inhomogeneities. Modelling of a thread-like heat conductive inhomogeneity is reduced to determination of density of heat distributed along a spatial curve, which replaces the inclusion. Corresponding boundary integral equations are obtained for anisotropic solids with thread-like inclusions. Non-integral terms are computed in a closed form. It is shown that, nevertheless the singularity of the equation is 1/r, it is hypersingular, since the kernel is symmetric. Boundary element approach is adopted for solution of the obtained equations. Numerical example is presented for a rectilinear conductive thread, which verifies derived boundary integral equations.
Źródło:
Acta Mechanica et Automatica; 2019, 13, 4; 251-254
1898-4088
2300-5319
Pojawia się w:
Acta Mechanica et Automatica
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
Improved algorithm for periodic steady-state analysis in nonlinear electromagnetic devices
Autorzy:
Sobczyk, T. J.
Radzik, M.
Powiązania:
https://bibliotekanauki.pl/articles/201260.pdf
Data publikacji:
2019
Wydawca:
Polska Akademia Nauk. Czytelnia Czasopism PAN
Tematy:
electromagnetic devices
steady-state analysis
periodic solutions
analysis in time domain
discrete differential operator
iterative algorithms
Opis:
This paper presents the improved methodology for the direct calculation of steady-state periodic solutions for electromagnetic devices, as described by nonlinear differential equations, in the time domain. A novel differential operator is developed for periodic functions and the iterative algorithm determining periodic steady-state solutions in a selected set of time instants is identified. Its application to steady-state analysis is verified by an elementary example. The modified algorithm reduces the complexity of steady-state analysis, particularly for electromagnetic devices described by high-dimensional nonlinear differential equations.
Źródło:
Bulletin of the Polish Academy of Sciences. Technical Sciences; 2019, 67, 5; 863-869
0239-7528
Pojawia się w:
Bulletin of the Polish Academy of Sciences. Technical Sciences
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
Numerical analysis of a serial connection of two staged SOFC stacks in a CHP system fed by methane using Aspen TECH
Autorzy:
Pianko-Oprych, Paulina
Palus, Mateusz
Powiązania:
https://bibliotekanauki.pl/articles/779502.pdf
Data publikacji:
2019
Wydawca:
Zachodniopomorski Uniwersytet Technologiczny w Szczecinie. Wydawnictwo Uczelniane ZUT w Szczecinie
Tematy:
Solid Oxide Fuel Cell stacks
Combined Heat and Power system
Balance of Plant
BoP
modelling
methane
Catalytic Partial Oxidation
CPOx
reformer
steam reformer
part and full load
steady state
dynamic model
Opis:
The objective of the study was to develop a steady-state system model in Aspen TECH using user-defined subroutines to predict the SOFC electrochemical performance. In order to achieve high overall fuel utilization and thus high electrical efficiency, a concept of Combined Heat and Power system with two-stage SOFC stacks of different number of cells was analyzed. The concept of two-stage SOFC stacks based system was developed in the framework of the FP7 EU-funded project STAGE-SOFC. The model was validated against data gathered during the operation of the proof-of-concept showing good agreement with the comparative simulation data. Following model validation, further simulations were performed for different values of fuel utilization to analyze its influence on system electrical performance. Simulation results showed that the concept of two-stage SOFC stacks configuration was viable and reliable. The model can be useful for development the optimal control strategy for system under safe conditions.
Źródło:
Polish Journal of Chemical Technology; 2019, 21, 1; 33-43
1509-8117
1899-4741
Pojawia się w:
Polish Journal of Chemical Technology
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
Steady state vibration of the periodically forced and damped pure nonlinear two-degrees-of-freedom oscillator
Autorzy:
Cveticanin, Livija
Zukovic, Miodrag
Cveticanin, Dragan
Powiązania:
https://bibliotekanauki.pl/articles/280690.pdf
Data publikacji:
2019
Wydawca:
Polskie Towarzystwo Mechaniki Teoretycznej i Stosowanej
Tematy:
non-harmonic excitation
force identification
steady-state motion
van der Pol oscillator
Duffing oscillator
Opis:
In the paper, a pure nonlinear and damped two-mass oscillator excited with a periodical force is considered. The oscillator is modelled with a system of two coupled second order nonlinear and non-homogenous equations. Using the model, two problems are investigated: one, identification of the excitation force for the known vibrating response of the system, and the second, determination of vibrations of the system excited with the known periodical force. Using the steady-state motion of the nonlinear oscillator, a method for identification of the excitation force is developed. For the pure nonlinear oscillator, it is obtained that the forcing function has the form of the Ateb function. However, if the excitation force is known, the procedure for computing the steady-state vibration of the system is introduced. The solution corresponds to steady-state vibrations of the free oscillator, but the amplitude and phase are assumed to be time variable. The averaged solutions are obtained for the pure nonlinear oscillator with an additional linear elastic force and for the van der Pol oscillator. Analytically obtained solutions are compared with numerical ones. They are in good agreement.
Źródło:
Journal of Theoretical and Applied Mechanics; 2019, 57, 2; 445-460
1429-2955
Pojawia się w:
Journal of Theoretical and Applied Mechanics
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
Wpływ charakterystyk eksploatacyjnych sieci przemysłowych na dobór parametrów filtrów harmonicznych
Impact of industrial network operating characteristics on the harmonic filter parameters sizing
Autorzy:
Warecki, Jurij
Gajdzica, Michał
Powiązania:
https://bibliotekanauki.pl/articles/268765.pdf
Data publikacji:
2019
Wydawca:
Politechnika Gdańska. Wydział Elektrotechniki i Automatyki
Tematy:
filtr wyższych harmonicznych
stany ustalone
stany przejściowe
bateria kondensatora
dławik filtrujący
harmonic filter
steady state
transients
capacitor bank
air-core filter reactor
Opis:
Układy kompensacji mocy biernej oraz filtracji, oparte na kondensatorach znajdują powszechne zastosowanie w praktycznych rozwiązaniach systemów przemysłowych. Ich parametry znamionowe wyznaczane są wyłącznie w oparciu o harmoniczne prądów oraz napięć w stanach ustalonych, niemniej jednak tyczy się to głównie jednostek filtrujących o prostej topologii. Stąd, mając na uwadze bardziej złożone układy w większości przypadków istniejących lub nowoprojektowanych obiektów wymaga się, aby analizowane układy były dostosowane do pracy zarówno w warunkach ustalonych jak i przejściowych. Korzystając ze standardów oraz norm, w artykule omówiono procedurę doboru parametrów baterii kondensatorów oraz dławików układów filtrujących z pozycji ich bezawaryjnej pracy w elektrycznych sieciach przemysłowych. Zaproponowana metoda ma wspomóż działania projektowe filtrów harmonicznych.
The application of harmonic filter circuit based on power capacitor banks are widely used in practical solutions in industrial systems. The component ratings of these units are often specified based solely on a combination of steady state fundamental and harmonic voltages and currents. Although, this may be adequate in single-tuned or single branch units and method may not properly rate the components for more complex applications such as multiple, single-tuned harmonic filter circuits in compensated installations. Thus, in the most cases of commonly used or newly designed circuits are required to be adapted to operate as well in steady state and transients conditions. Using the exsisting Standards, the article propose a method for determining equipment ratings parameters of the capacitor banks and air-core filter reactors according to malfunctions. The study illustrated in this paper will be used to support and improve harmonic filter realiability and design. It is hoped that ideas will be a resource for a future filter application guide being contemplated by the capacitor subcommittee.
Źródło:
Zeszyty Naukowe Wydziału Elektrotechniki i Automatyki Politechniki Gdańskiej; 2019, 67; 47-51
1425-5766
2353-1290
Pojawia się w:
Zeszyty Naukowe Wydziału Elektrotechniki i Automatyki Politechniki Gdańskiej
Dostawca treści:
Biblioteka Nauki
Artykuł

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