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Wyszukujesz frazę "dynamics analysis" wg kryterium: Temat


Tytuł:
Analysis of the single stage cycloidal gearbox with lobe defects. Fault diagnosis attempts using coherence function and Morris minimum-bandwidth wavelets
Autorzy:
Król, Roman
Powiązania:
https://bibliotekanauki.pl/articles/27309893.pdf
Data publikacji:
2023
Wydawca:
Polska Akademia Nauk. Czasopisma i Monografie PAN
Tematy:
cycloidal gearbox
frequency analysis
coherence
wavelets
multibody dynamics
przekładnia cykloidalna
analiza częstotliwości
dynamika wieloczłonowa
Opis:
In this article, the frequency characteristics of the forces and torques in the various cycloidal gearbox designs were investigated. The aim of the article is the search for frequency patterns that could be used in the formulation of a fault diagnosis methodology. Numerical analysis was performed in the cycloidal gearbox without defects as well as in cycloidal gearboxes with lobe defects or with removed lobes. The results of the numerical analysis were obtained in the multibody dynamics model of the cycloidal gearbox, implemented in Fortran and using the 2nd-order Runge-Kutta method for the integration of the motion equations. The used model is planar and uses Hunt and Crossley’s nonlinear contact modelling algorithm, which was modified using the Heaviside function and backlash to fit cycloidal gearbox model convergence demands. In the analysis of fault diagnosis methods, the coherence function and Morris minimum-bandwidth wavelets were used. It is difficult to find a unique pattern in the results to use in the fault diagnosis because of the random characteristics of the torques at the input and output shafts. Based on obtained results, a promising, low-vibration cycloidal gearbox design with removed 7 lobes of the single wheel was studied using the FFT algorithm.
Źródło:
Archive of Mechanical Engineering; 2023, LXX, 3; 409--431
0004-0738
Pojawia się w:
Archive of Mechanical Engineering
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
Comparison of Wear Resistance in Polycrystalline and Monocrystalline Iron
Autorzy:
Liu, Zhiming
Zhang, Qiang
Liu, Fangying
Zhang, Hezhe
Powiązania:
https://bibliotekanauki.pl/articles/2203723.pdf
Data publikacji:
2023
Wydawca:
Polska Akademia Nauk. Czytelnia Czasopism PAN
Tematy:
molecular dynamics
polycrystalline
centro symmetric analysis
abrasive wear
Opis:
In the present research, we used molecular dynamics simulation to determine the effect of cutting parameters on micro-grain boundary structures and Burgers vector distribution in single crystal iron and polycrystalline iron materials. The result showed that the destruction of the lattice in polycrystalline iron caused by the cutting tool was restricted to the contact surface area. In addition, in the precision machining process, a higher refining grain was observed on the iron surface. During the cutting process of single crystal iron, large-scale slip occurred along the <111> crystal direction on the {110} crystal plane. And the slip presented an annular shape.
Źródło:
Archives of Metallurgy and Materials; 2023, 68, 1; 15--20
1733-3490
Pojawia się w:
Archives of Metallurgy and Materials
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
Evaluation of wind effects on buildings using design codes and numerical wind tunnel tests
Ocena wpływu wiatru na budynki z wykorzystaniem norm projektowych i testów numerycznych w metodzie tunelu aerodynamicznego
Autorzy:
Hossain, Imam
Islam, Jahidul
Amin, Al
Powiązania:
https://bibliotekanauki.pl/articles/27314901.pdf
Data publikacji:
2023
Wydawca:
Politechnika Świętokrzyska w Kielcach. Wydawnictwo PŚw
Tematy:
wind load analysis
wind tunnel test
wind simulation
reinforced cement concrete structure
computational fluid dynamics
Bangladesh National Building Code
analiza obciążenia wiatrem
test w tunelu aerodynamicznym
symulacja oddziaływania wiatru
konstrukcja żelbetowa
obliczeniowa dynamika płynów
bangladeska krajowa norma budowlana
Opis:
The evaluation of wind effect on the regular shape and simple diaphragm buildings and structures due to wind load has been calculated by several international codes and standards where wind gust nature and dynamic effect could not capture. Bangladesh National Building Code (BNBC) provides the tools for engineers to calculate the wind pressures for the design of a regular-shaped structure with a height to width ratio of less than 5.0, a simple diaphragm, and no unusual geometrical irregularity. If these conditions do not satisfy a wind tunnel testing is required. In this study, a comparative study between two codes in Bangladesh (BNBC-2006 and BNBC-2020), and wind tunnel test results are conducted. An investigation is carried out on four typical buildings with variable heights located within Dhaka, Bangladesh. A computational fluid dynamics (CFD) program RWIND is used to calculate the wind loads on buildings and are compared with those obtained by Bangladesh National Building Codes. Storey shear of four different building models is compared. Between BNBC-2006 and BNBC-2020, there is up to a 53% difference in storey shear. Whereas, up to 30% variation in storey shear is observed between the numerical wind tunnel test data and the data calculated using the BNBC-2020 equations. Finally, this study will help in improving BNBC code provisions for wind load calculations.
Kalkulację wpływu wiatru na budynki i budowle o regularnych kształtach i prostych konstrukcjach pod obciążeniem wiatrem przedstawiono w kilku normach międzynarodowych, w których jednak nie uwzględniono charakteru podmuchów wiatru i efektu dynamicznego. Bangladeska Krajowa Norma Budowlana (BNBC) zapewnia inżynierom narzędzia do obliczania ciśnienia wiatru przy projektowaniu konstrukcji o regularnym kształcie, o stosunku wysokości do szerokości mniejszym niż 5,0, prostej konstrukcji oraz bez nietypowych nieregularności geometrycznych. Jeśli warunki te nie są spełnione, wymagane jest przeprowadzenie testów w tunelu aerodynamicznym. W niniejszym opracowaniu przeprowadzono badanie porównawcze między dwiema normami obowiązującymi w Bangladeszu (BNBC-2006 i BNBC-2020) oraz wynikami testów w tunelu aerodynamicznym. Badanie przeprowadzono na czterech typowych budynkach o różnej wysokości zlokalizowanych w Dhace w Bangladeszu. Program RWIND do obliczeń i symulacji dynamiki płynów (CFD) został wykorzystany do obliczenia obciążeń wiatrem na budynkach i porównany z wynikami uzyskanymi według bangladeskich norm budowlanych. Porównano ścinanie kondygnacji czterech różnych modeli budynków. W tym względzie różnice pomiędzy BNBC-2006 i BNBC-2020 wynoszą do 53%. Natomiast między danymi z numerycznego testu w tunelu aerodynamicznym a danymi obliczonymi przy użyciu równań BNBC-2020 zaobserwowano do 30% różnic w odniesieniu do ścinania kondygnacji. Badanie to pomoże też ulepszyć przepisy norm BNBC dotyczące obliczeń obciążenia wiatrem.
Źródło:
Structure and Environment; 2023, 15, 2; 73--81
2081-1500
Pojawia się w:
Structure and Environment
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
Investigation of the pad stiffness effects on the initiation of brake squeal phenomenon
Autorzy:
Yavuz, Akif
Sen, Osman
Powiązania:
https://bibliotekanauki.pl/articles/2200884.pdf
Data publikacji:
2023
Wydawca:
Polskie Towarzystwo Mechaniki Teoretycznej i Stosowanej
Tematy:
disc brake squeal
mode coupling phenomenon
linear stability analysis
nonlinear dynamics
Opis:
The main objective of this study is to investigate pad stiffness effects on the instability of a nonlinear brake squeal model. Hence, a nonlinear mathematical model is developed. The nonlinear model is linearized to check the system stability through complex eigenvalue analysis. The results of linear stability analyses are compared to the numerical solution of the nonlinear model, and it is observed that the dynamic behavior predicted by the linear stability analysis is in accordance with the numerical solutions. Though, a discrepancy may occur at the predicted squeal frequencies with both approaches, especially at high pad stiffness levels.
Źródło:
Journal of Theoretical and Applied Mechanics; 2023, 61, 2; 219--232
1429-2955
Pojawia się w:
Journal of Theoretical and Applied Mechanics
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
The impact of water quality on the availability of phytoplankton and growth of Litopenaeus vannamei
Autorzy:
Musa, Muhammad
Thoyibah, Auliarifka A.
Puspitaningtyas, Dyah A.
Arsad, Sulastri
Mahmudi, Mohammad
Lusiana, Evellin D.
Maftuch, Maftuch
Huda, Agus S.
Powiązania:
https://bibliotekanauki.pl/articles/2203547.pdf
Data publikacji:
2023
Wydawca:
Instytut Technologiczno-Przyrodniczy
Tematy:
algae
aquaculture
canonical correspondence analysis
CCA
dynamics of water quality
principal component analysis
PCA
vannamei shrimp
Opis:
This research analysed the availability of phytoplankton and the growth rate of Vannamei shrimp in relation to water quality changes. The research was carried out in February-March 2021 for a half cycle of shrimp cultivation in two ponds of the Brackish Water Fish Culture Probolinggo Laboratory in Probolinggo, East Java, Indonesia. The research used a descriptive method and included a survey. Sampling was made every two weeks for two months. Nine parameters were measured and ten shrimps were taken for a specific growth rate (SGR) measurement once per sampling. Data were analysed using the principal component analysis (PCA) and canonical correspondence analysis (CCA). Secondary data of water quality were added for the PCA. The results show that the phytoplankton found in the first pond consisted of Chlorophyta, Chrysophyta, and Cyanophyta, whereas the phytoplankton in the other pond included Chlorophyta, Chrysophyta, Cyanophyta, and Dinophyta. The abundance of phytoplankton ranged from 12-80∙103 cell∙cm-3, which indicated eutrophic waters. The PCA demonstrated that pH, nitrate, and total organic matter (TOM) significantly influenced phytoplankton abundance in the pond. In addition, water quality parameters, such as temperature, transparency, salinity, nitrite and phosphate levels, were tolerable in both ponds for the growth of shrimps. However, the level of pH was lower than the aquaculture quality standard, whereas those of nitrate, ammonia, and TOM were higher. The growth rate of Vannamei shrimp increased by 0.76–7.34%∙day-1.
Źródło:
Journal of Water and Land Development; 2023, 56; 127--135
1429-7426
2083-4535
Pojawia się w:
Journal of Water and Land Development
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
Analiza porównawcza sposobów wyznaczania obciążeń wiatrem na podstawie norm projektowych i analizy przepływu CFD
Comparative analysis of the methods of determining wind loads on the basis of design standards and CFD flow analysis
Autorzy:
Okoński, Robert
Ambroziak, Andrzej
Powiązania:
https://bibliotekanauki.pl/articles/2081880.pdf
Data publikacji:
2022
Wydawca:
Polski Związek Inżynierów i Techników Budownictwa
Tematy:
analiza CFD
numeryczna mechanika płynów
obciążenie wiatrem
PN-EN 1991-1-4
R-Wind Simulation
model budynku
nachylenie dachu
dach dwuspadowy
współczynnik parcia
CFD analysis
computational fluid dynamics
wind load
building model
roof slope
gable roof
pressure coefficient
Opis:
W pracy poruszono tematykę wykorzystania analizy przepływu CFD do wyznaczania obciążeń wiatru na konstrukcje. Przedstawiono analizę trzech modeli budynków o dachu dwuspadowym o różnych kątach nachylenia, dla których dokonano porównania wielkości współczynników parcia z wynikami dostępnymi w literaturze. Obliczenia analityczne wykonano zgodnie z normą z PN-EN 1991-1-4, natomiast obliczenia numeryczne wykonano w programie R-Wind Simulation. Całość wyników podsumowano, a wnioski sformułowano w odniesieniu do tematyki rozwiązania problemu szacowania wielkości obciążenia wiatru działającego na konstrukcję.
The paper addresses the use of CFD flow analysis to determine wind loads on structures. Three models of buildings with a gable roof with different angles of inclination were presented, for which the size of the pressure coefficients was compared with the results available in the literature. The analytical calculations were made in accordance with the PN-EN 1991-1-4 standard, while the numerical calculations were made in the R-Wind Simulation program. All the results were summarized and the conclusions were formulated in relation to the problem of solving the problem of estimating the size of the wind load acting on the structure.
Źródło:
Przegląd Budowlany; 2022, 93, 3-4; 46--57
0033-2038
Pojawia się w:
Przegląd Budowlany
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
Analysis of the backlash in the single stage cycloidal gearbox
Autorzy:
Król, Roman
Powiązania:
https://bibliotekanauki.pl/articles/27309870.pdf
Data publikacji:
2022
Wydawca:
Polska Akademia Nauk. Czasopisma i Monografie PAN
Tematy:
cycloidal gearbox
backlash
dynamics
multibody dynamics
multibody simulation
discrete Fourier transform
spectral analysis
FFT
przekładnia cykloidalna
reakcja
dynamika
dynamika wieloczłonowa
symulacja wieloobiektowa
dyskretna transformata Fouriera
analiza spektralna
Opis:
In this paper the analysis of backlash influence on the spectrum of torque at the output shaft of a cycloidal gearbox has been performed. The model of the single stage cycloidal gearbox was designed in the MSC Adams. The analysis for the excitation with the torque and the analysis with constant angular velocity of the input shaft were performed. For these analyses, the amplitude spectrums of the output torque for different backlashes was solved using FFT algorithm. The amplitude spectrums of the combined sine functions composed of the impact to impact times between the cycloidal wheel and the external sleeves were computed for verification. The performed studies show, that the backlash has significant influence on the output torque amplitude spectrum. Unfortunately the dependencies between the components of the spectrum and the backlash could not be expressed by linear equations, when vibrations of the output torque in the range of (350 Hz – 600 Hz) are considered. The gradual dependence can be found in the spectrum determined for the combined sine functions with half-periods equal impact-to-impact times. The spectrum is narrower for high values of backlash.
Źródło:
Archive of Mechanical Engineering; 2022, LXIX, 4; 693--711
0004-0738
Pojawia się w:
Archive of Mechanical Engineering
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
Comparable analysis of PID controller settings in order to ensure reliable operation of active foil bearings
Autorzy:
Witanowski, Łukasz
Breńkacz, Łukasz
Szewczuk-Krypa, Natalia
Dorosińska-Komor, Marta
Puchalski, Bartosz
Powiązania:
https://bibliotekanauki.pl/articles/2087023.pdf
Data publikacji:
2022
Wydawca:
Polska Akademia Nauk. Polskie Naukowo-Techniczne Towarzystwo Eksploatacyjne PAN
Tematy:
gas foil bearings
operation stability
PID controller
optimization
rotor dynamics
comparable analysis
Opis:
In comparison to the traditional solutions, active bearings offer great operating flexibility, ensure better operating conditions over a wider range of rotational speeds and are safe to use. In order to ensure optimum bearing performance a bearing control system is used that adapts different geometries during device operation. The selection of optimal controller parameters requires the use of modern optimization methods that make it possible to quickly achieve the assumed parameters. This article presents the method that has been employed to select the parameters of a proportional integral derivative (PID) controller, in which both stochastic algorithms and hybrid methods have been compared. The results show that all of the used algorithms were able to reach the global optimum but only the hybrid algorithm was repeatable in all runs within a low value of the standard deviation. The best solution will be proposed in the future to control an active foil bearing. Analysing of this paper would help to prevent failures of active foil bearing used in the designed rotating machine.
Źródło:
Eksploatacja i Niezawodność; 2022, 24, 2; 377--385
1507-2711
Pojawia się w:
Eksploatacja i Niezawodność
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
Dynamic Analysis of the Starting and Braking of the Table of CNC Machine Tool
Autorzy:
Józwik, Jerzy
Zawada-Michałowska, Magdalena
Moń, Damian
Powiązania:
https://bibliotekanauki.pl/articles/2201776.pdf
Data publikacji:
2022
Wydawca:
Stowarzyszenie Inżynierów i Techników Mechaników Polskich
Tematy:
dynamics analysis
vision systems
CNC machine tool
feed rate
CNC machine tools accuracy
CNC machine table
Opis:
The aim of the paper is a dynamic analysis of the starting and braking of the table of a numerically controlled CNC machine tool during idle motion. The experimental test was performed on the vertical table of the FV580A machining centre using the Phantom v1610 high-speed vision camera. The dynamics characteristics of the table movement were registered and the dynamics estimates of the movement were determined. The influence estimation of the parameters of the machine tool table motion on the value of the determined estimates was made. The results of measurements were discussed and guidelines and in order to minimise disturbances were formulated. The test results were summarised and discussed in the form of charts and tables. The directions of further research in the discussed subject area were also defined
Źródło:
Advances in Science and Technology. Research Journal; 2022, 16, 3; 34--46
2299-8624
Pojawia się w:
Advances in Science and Technology. Research Journal
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
Dynamics of pertinent project delay variables in the Thai construction sector: mathematical analysis
Autorzy:
Ajayi, Babatunde Oluwaseun
Chinda, Thanwadee
Powiązania:
https://bibliotekanauki.pl/articles/2105324.pdf
Data publikacji:
2022
Wydawca:
Politechnika Białostocka. Oficyna Wydawnicza Politechniki Białostockiej
Tematy:
construction delay
DEMATEL analysis
system dynamics
preconstruction
project management
poóźnienie budowlane
analiza DEMATEL
dynamika układu
przekonstrukcje
zarządzanie projektem
Opis:
Project completion behind schedule is a struggle for the construction sector, affecting time, cost, and quality. This investigation has been necessitated by the lingering nature of project delay risks despite many extant analyses. This study collated expert opinions from the Thai construction sector on salient construction delay variables and their influence on each other for DEMATEL-SD analysis. The collated data were analysed and found consistent with a Cronbach’s alpha of 0.939. Then, the DEMATEL technique was used to establish the influence weight of factors for the System dynamics (SD) analysis. It was discovered that minimising the design error at the preconstruction stage significantly reduces the magnitude of delay. Increasing values of design error and change order increase the rework profile. Besides, the project delivery within the scheduled 232 weeks can be ensured by minimising the threat of design error, design change, change order, rework, productivity problem, and by improving project management. This study adopted a hybrid mathematical system to holistically examine the construction delay risk by comprehensively exploring the dynamics of influencing variables and investigating their impact on the project scheme. The system helps project stakeholders to arrive at an effective decision in overcoming delay risks, thus minimising the cost overrun and improving the project quality.
Źródło:
Engineering Management in Production and Services; 2022, 14, 2; 26--45
2543-6597
2543-912X
Pojawia się w:
Engineering Management in Production and Services
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
Effect of Nanoindentation Rate on Plastic Deformation in Cu Thin Films
Autorzy:
Chocyk, Dariusz
Zientarski, Tomasz
Powiązania:
https://bibliotekanauki.pl/articles/2022488.pdf
Data publikacji:
2022
Wydawca:
Stowarzyszenie Inżynierów i Techników Mechaników Polskich
Tematy:
nanoindentation
stress distribution
dislocation
common neighbor analysis
molecular dynamics simulation
Cu
thin film
Opis:
The paper investigates the nanoindentation process with different rates in the Cu (001) of FCC system. The indentation process was done using molecular dynamics simulation based on the embedded atom method theory and Morse potential. Simulation process of indentation used a rigid spherical indenter with the diamond structure. To structure characterization we applied the adaptive common neighbour and the dislocation extraction analysis. It was found that the range of the linear change of the indentation force depends on the rate of response of the system. The initial range of the linear dependence of stress evolution also depends on the rate of indentation. Moreover, the average total normal stress in the system is only compressive. After linear changes, we observe oscillating changes in stress evolution. During indentation, for the range of linear changes of stress, dislocations aggregated only around the indenter surface. The creation of dislocations is directly connected with the structural changes. The structure analysis revealed the formation of HCP and BCC structure in the Cu (001) of FCC systems and a correlation with the creation of dislocations.
Źródło:
Advances in Science and Technology. Research Journal; 2022, 16, 1; 170-179
2299-8624
Pojawia się w:
Advances in Science and Technology. Research Journal
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
Niestandardowa analiza minigrupy fokusowej i triady na przykładzie społeczności wielowyznaniowej
A Non-Standard Analysis of a Mini-Focus-Group and a Triad Based on the Example of a Multiconfessional Community
Autorzy:
Orzechowski, Paweł
Powiązania:
https://bibliotekanauki.pl/articles/2105619.pdf
Data publikacji:
2022-05-31
Wydawca:
Uniwersytet Łódzki. Wydawnictwo Uniwersytetu Łódzkiego
Tematy:
zogniskowany wywiad grupowy
dynamika grupowa
wielowyznaniowość
analiza konwersacji i dyskursu
transkrypcje
(focus group interview)
group dynamics
multiconfessionalism
conversation and discourse analysis
transcriptions
Opis:
Niniejszy artykuł odnosi się przede wszystkim do metody minigrup fokusowych i triady, stanowiących odmiany zogniskowanych wywiadów grupowych, które w ciągu ostatnich lat zyskały na popularności nie tylko w marketingu i szeroko pojętej sferze komercyjnej, ale również w świecie akademickim. Zastosowaniu tego typu wywiadów nie towarzyszy jednak nadal pogłębiona refleksja naukowa, co sprawia, że mają zarówno zagorzałych zwolenników, jak i przeciwników. Głównym zamiarem autora jest przynajmniej częściowe zapełnienie powstałej luki. Poprzez połączenie trzech typów analiz: dynamiki grupowej, konwersacji i dyskursu (topików) zaproponowano czytelnikowi niestandardowe podejście do pracy nad transkrypcjami pochodzącymi z dyskusji fokusowych. Odbiorca znajdzie w niniejszym tekście odniesienie do wyników badań własnych autora, przeprowadzonych w 2020 roku w wybranej społeczności lokalnej zróżnicowanej wyznaniowo. W części poświęconej analizie dyskursu zostaną ponadto pogłębione techniczne i praktyczne aspekty związane z przedstawionym podejściem analitycznym.
This article relates primarily to the mini-focus groups and triads, which constitute variations of focus group interviews, which in recent years have gained popularity not only in marketing and the broadly understood commercial sphere, but also in the academic world. However, the use of this type of interviews is still not accompanied by in-depth scientific reflection; as a result, they have acquired both staunch supporters and opponents. The author’s main intention is to fill the resultant gap, at least partially. By combining three types of analysis – i.e. group dynamics, conversation, and discourse (topics) – the Reader is offered a non-standard attitude to working with transcripts which come from focus discussions. The Reader will find in this text a reference to the results of the author’s own research, carried out in 2020 among selected multiconfessional local community. In the part dedicated to discourse analysis, the technical and practical aspects related to the presented analytical approach will also be deepened.
Źródło:
Przegląd Socjologii Jakościowej; 2022, 18, 2; 26-53
1733-8069
Pojawia się w:
Przegląd Socjologii Jakościowej
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:
Optimization of gear teeth in the wind turbine drive train with gear contact’s uncertainty using the reliability-based design optimization
Autorzy:
Lee, Changwoo
Park, Yonghui
Powiązania:
https://bibliotekanauki.pl/articles/27309867.pdf
Data publikacji:
2022
Wydawca:
Polska Akademia Nauk. Czasopisma i Monografie PAN
Tematy:
wind turbine
drive train
gear
structural analysis
dynamics
Fourier transform
reliability based design optimization
turbina wiatrowa
układ napędowy
bieg
analiza strukturalna
dynamika
optymalizacja projektu oparta na niezawodności
Opis:
Although gear teeth give lots of advantages, there is a high possibility of failure in gear teeth in each gear stage in the drive train system. In this research, the authors developed proper gear teeth using the basic theorem of gear failure and reliability-based design optimization. A design variable characterized by a probability distribution was applied to the static stress analysis model and the dynamics analysis model to determine an objective function and constraint equations and to solve the reliability-based design optimization. For the optimization, the authors simulated the torsional drive train system which includes rotational coordinates. First, the authors established a static stress analysis model which gives information about endurance limit and bending strength. By expressing gear mesh stiffness in terms of the Fourier series, the equations of motion including the gear mesh models and kinematical relations in the drive train system were acquired in the form of the Lagrange equations and constraint equations. For the numerical analysis, the Newmark Beta method was used to get dynamic responses including gear mesh contact forces. From the results such as the gear mesh contact force, the authors calculated the probability of failure, arranged each probability and gear teeth, and proposed a reasonable and economic design of gear teeth.
Źródło:
Archive of Mechanical Engineering; 2022, LXIX, 4; 713--728
0004-0738
Pojawia się w:
Archive of Mechanical Engineering
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
The structure of Pb-PbO-SiO2 glass via molecular dynamics simulation
Autorzy:
Rybicki, J.
Witkowska, A.
Bergmański, G.
Mancini, G.
Feliziani, S.
Powiązania:
https://bibliotekanauki.pl/articles/1954650.pdf
Data publikacji:
2022-01-20
Wydawca:
Politechnika Gdańska
Tematy:
lead-silicate glasses
oxide glasses
medium-range order
ring analysis
molecular dynamics simulations
Opis:
The paper is dedicated to a molecular dynamics (MD) study of the structure of partially reduced lead-silicate glass of composition 1Pb 1PbO 1SiO2. The simulations have been performed in the constant volume regime, using a two-body potential (Born-Mayer repulsive forces, and Coulomb forces due to full ionic charges). The system was initially prepared as a well equilibrated hot melt, and then slowly cooled down to 300K. The information on short-range correlations were obtained in a conventional way (from pair and angular distribution functions), while the medium-range order was studied via cation-anion ring analysis. In the paper, the short- and medium-range order in the simulated system is discussed and compared with the structure of a glassy completely reduced system, i.e. 2Pb 1SiO2 and unreduced one, i.e. 2PbO 1SiO2 glass.
Źródło:
TASK Quarterly. Scientific Bulletin of Academic Computer Centre in Gdansk; 2003, 7, 2; 243-256
1428-6394
Pojawia się w:
TASK Quarterly. Scientific Bulletin of Academic Computer Centre in Gdansk
Dostawca treści:
Biblioteka Nauki
Artykuł

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