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Tytuł:
A CFD package for the 3D Navier-Stokes computation of unsteady flows in turbomachines
Autorzy:
Thermann, H.
Schmidt, S.
Weiss, C.
Niehuis, R.
Powiązania:
https://bibliotekanauki.pl/articles/1967647.pdf
Data publikacji:
2001
Wydawca:
Politechnika Gdańska
Tematy:
CFD
computational fluid dynamics CFD
turbomachinery
laminar-to-turbulent transition
flutter
clocking
Navier-Stokes package
Opis:
A 3D Navier-Stokes package for the time-accurate computation of unsteady flows in turbomachines with emphasis on wide applicability, portability and efficiency is presented. The package consists of three components: the elliptic grid generator FRAME, the parallelised implicit Reynolds- and Favre-averaged Navier-Stokes solver PANTA and the post-processor TREAT especially designed for unsteady flow phenomena. The applicability of the package covers both rotor/stator interaction and blade flutter phenomena in multirow and multipassage 2D, Quasi3D and general 3D configurations in a wide range of flow velocities (subsonic, transonic). For turbulent computations either a Low-Reynolds-Number k-" or k-! turbulence model is available. Additionally, an algebraic transition model can be chosen from a variety of different models to enhance the accuracy of prediction for transitional flow phenomena. A description of the underlying algorithms and numerical methods as well as the main features and characteristics of each of the three components is given. Furthermore, selected examples of typical turbomachinery applications are shown to demonstrate these features.
Źródło:
TASK Quarterly. Scientific Bulletin of Academic Computer Centre in Gdansk; 2001, 5, 4; 537-547
1428-6394
Pojawia się w:
TASK Quarterly. Scientific Bulletin of Academic Computer Centre in Gdansk
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
A complete design of contra-rotating propellers using the new computer system
Autorzy:
Koronowicz, T.
Krzemianowski, Z.
Tuszkowska, T.
Szantyr, J. A.
Powiązania:
https://bibliotekanauki.pl/articles/259381.pdf
Data publikacji:
2010
Wydawca:
Politechnika Gdańska. Wydział Inżynierii Mechanicznej i Okrętownictwa
Tematy:
ship propellers
contra-rotating propellers
esign methods
computational fluid dynamics (CFD)
Opis:
The computer system for the complete design of the contra-rotating propellers presented in this article has several common blocks and procedures with the systems for design of single propellers and tandem corotating propellers, presented in detail in the Polish Maritime Research No.1 and No.4 of the Volume 16, 2009. In this article only the blocks and procedures developed specially for the contra-rotating propellers are described. The system is based on the lifting line and lifting surface models and on the Computational Fluid Mechanics methods. The comparative analysis of the contra-rotating propellers and the tandem corotating propellers is included.
Źródło:
Polish Maritime Research; 2010, 1; 14-24
1233-2585
Pojawia się w:
Polish Maritime Research
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
A complete design of ducted propellers using the new computer system
Autorzy:
Koronowicz, T.
Krzemianowski, Z.
Tuszkowska, T.
Szantyr, J. A.
Powiązania:
https://bibliotekanauki.pl/articles/258682.pdf
Data publikacji:
2009
Wydawca:
Politechnika Gdańska. Wydział Inżynierii Mechanicznej i Okrętownictwa
Tematy:
ship propellers
ducted propellers
design methods
computational fluid dynamics (CFD)
Opis:
The computer system for the completed design of the ducted ship propellers has some common blocks and procedures with the analogical system for open propellers that has already been presented in detail in the Polish Maritime Research [1]. This article describes only these blocks and procedures which are specific for the design of ducted propellers. These new blocks concern first of all the procedures for the design calculation of ducted propellers and for the analysis of the ducted propeller operation in the non-uniform velocity field behind the ship hull. The comparative analysis of computation results for different types of ducts is also presented.
Źródło:
Polish Maritime Research; 2009, 2; 34-39
1233-2585
Pojawia się w:
Polish Maritime Research
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
A complete design of ship propellers using the new computer system
Autorzy:
Koronowicz, T.
Krzemianowski, Z.
Tuszkowska, T.
Szantyr, J. A.
Powiązania:
https://bibliotekanauki.pl/articles/258618.pdf
Data publikacji:
2009
Wydawca:
Politechnika Gdańska. Wydział Inżynierii Mechanicznej i Okrętownictwa
Tematy:
ship propellers
design methods
computational fluid dynamics (CFD)
Opis:
The computer system presented in this article is composed of several program blocks for the complete design of ship propellers. The design calculations are based on a combination of the modified lifting line theory and on the vortex lifting surface theory. The system enables solution of the following design problems: - calculation of the scale effect on the ship wake velocity field, including the influence of the propeller and rudder on this field at the propeller location - maximization of the propulsive efficiency - optimization of the propeller blade geometry on the basis of the compromise between the cavitation and blade strength requirements - optimization of the number of propeller blades and blade geometry on the basis of the acceptable level of induced pressure pulses and unsteady shaft bearing forces - calculation of the blade spindle torque for the controllable pitch propellers. The computer system is equipped with many numerical options for graphical visualization of the input data, including an easy possibility of their correction and control of the intermediate and final results of calculations.
Źródło:
Polish Maritime Research; 2009, 1; 29-34
1233-2585
Pojawia się w:
Polish Maritime Research
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
A complete design of tandem co-rotating propellers using the new computer system
Autorzy:
Koronowicz, T.
Krzemianowski, Z.
Tuszkowska, T.
Powiązania:
https://bibliotekanauki.pl/articles/259409.pdf
Data publikacji:
2010
Wydawca:
Politechnika Gdańska. Wydział Inżynierii Mechanicznej i Okrętownictwa
Tematy:
ship propellers
tandem co-rotating propellers
design methods
computational fluid dynamics (CFD)
Opis:
The computer system for the complete design of the tandem co-rotating propellers, presented in this article, has several common blocks and procedures with the computer system for the design of conventional single propellers, presented in detail in Polish Maritime Research No. 1 Vol. 16 (2009). In this article only these blocks and procedures are described, which are different in both systems. The comparative analysis of the designed tandem propeller and a conventional propeller is also included.
Źródło:
Polish Maritime Research; 2010, 4; 17-25
1233-2585
Pojawia się w:
Polish Maritime Research
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
A computational evaluation of sedentary lifestyle effects on carotid hemodynamics and atherosclerotic events incidence
Autorzy:
Caruso, M. V.
Serra, R.
Perri, P.
Buffone, G.
Calio, F. G.
Franciscis, S.
Fragomeni, G.
Powiązania:
https://bibliotekanauki.pl/articles/307512.pdf
Data publikacji:
2017
Wydawca:
Politechnika Wrocławska. Oficyna Wydawnicza Politechniki Wrocławskiej
Tematy:
siedzący tryb życia
pozycja siedząca
komputerowa mechanika płynów
CFD
miażdżyca
sedentary lifestyle
sitting
computational fluid dynamics
carotid bifurcation
atherosclerosis
standing
Opis:
Purpose: Hemodynamics has a key role in the atheropathogenesis. Indeed, atherosclerotic phenomena occur in vessels characterized by complex geometry and flow pattern, like the carotid bifurcation. Moreover, the lifestyle is a significant risk factor. The aim of this study is to evaluate the hemodynamic effects due to two sedentary lifestyles -sitting and standing positions- in the carotid bifurcation in order to identify the worst condition and to investigate the atherosclerosis incidence. Methods: The computational fluid dynamics (CFD) was chosen to carry out the analysis, in which in-vivo non-invasive measurements were used as boundary conditions. Furthermore, to compare the two conditions, one patient-specific 3D model of a carotid bifurcation was reconstructed starting from computer tomography. Different mechanical indicators, correlated with atherosclerosis incidence, were calculated in addition to flow pattern and pressure distribution: the time average wall shear stress (TAWSS), the oscillatory shear index (OSI) and the relative residence time (RRT). Results: The results have highlighted that the bulb and the external carotid artery emergence are the most probable regions in which atherosclerotic events could happen. Indeed, low velocity and WSS values, high OSI and, as a consequence, areas with chaotic-swirling flow, with stasis (high RRT), occur. Moreover, the sitting position is the worst condition: considering a cardiac cycle, TAWSS is less than 17.2% and OSI and RRT are greater than 17.5% and 21.2%, respectively. Conclusions: This study suggests that if a person spends much time in the sitting position, a high risk of plaque formation and, consequently, of stenosis could happen.
Źródło:
Acta of Bioengineering and Biomechanics; 2017, 19, 3; 43-52
1509-409X
2450-6303
Pojawia się w:
Acta of Bioengineering and Biomechanics
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
A Method of Assessment of the Liquid Sloshing Impact on Ship Transverse Stability
Autorzy:
Krata, P.
Powiązania:
https://bibliotekanauki.pl/articles/117159.pdf
Data publikacji:
2014
Wydawca:
Uniwersytet Morski w Gdyni. Wydział Nawigacyjny
Tematy:
ship operation
liquid sloshing phenomenon
liquid sloshing
computational fluid dynamics (CFD)
hydrodynamics
ship stability
ship transverse stability
dynamic heeling moment
Opis:
Liquid sloshing phenomenon taking place in partly filled ships’ tanks directly affects the stability of a vessel. However, only static calculations are carried out onboard ships nowadays and static transfer of liquid weight is taken into account in the course of routine stability calculation. The paper is focused on a dynamic heeling moment due to liquid sloshing in tanks onboard ships. The set of numerical simulations of liquid sloshing taking place in moving tanks is carried out. The realistic range of geometric parameters is taken into account. The conducted CFD simulations are experimentally verified. Finally, the method of an assessment of the liquid sloshing impact on ship transverse stability is worked out. The key point of the method is a dynamic coefficient describing relation of the researched dynamic heeling moment and the quasi-static one in terms of dynamic stability of a vessel which is related to the weather criterion of ship stability assessment.
Źródło:
TransNav : International Journal on Marine Navigation and Safety of Sea Transportation; 2014, 8 no. 4; 535-541
2083-6473
2083-6481
Pojawia się w:
TransNav : International Journal on Marine Navigation and Safety of Sea Transportation
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
A review of the numerical studies on planar and tubular solid oxide fuel cells within four EU projects of the 7th framework programme
Autorzy:
Pianko-Oprych, P.
Jaworski, Z.
Zinko, T.
Palus, M.
Powiązania:
https://bibliotekanauki.pl/articles/185086.pdf
Data publikacji:
2018
Wydawca:
Polska Akademia Nauk. Czytelnia Czasopism PAN
Tematy:
Solid Oxide Fuel Cell
stack
fuel cell system
Computational Fluid Dynamics
CFD
Finite Element Method
FEM
modelling
process simulation
ogniwo paliwowe z tlenkiem stałym
system ogniw paliwowych
obliczeniowa dynamika płynów
metoda elementów skończonych
MES
modelowanie symulacje procesu
Opis:
The paper addresses the issues of quantification and understanding of Solid Oxide Fuel Cells (SOFC) based on numerical modelling carried out under four European, EU, research projects from the 7FP within the Fuel Cell and Hydrogen Joint Undertaking, FCH JU, activities. It is a short review of the main projects’ achievements. The goal was to develop numerical analyses at a single cell and stack level. This information was integrated into a system model that was capable of predicting fuel cell phenomena and their effect on the system behaviour. Numerical results were analysed and favourably compared to experimental results obtained from the project partners. At the single SOFC level, a static model of the SOFC cell was developed to calculate output voltage and current density as functions of fuel utilisation, operational pressure and temperature. At the stack level, by improving fuel cell configuration inside the stack and optimising the operation conditions, thermal stresses were decreased and the lifetime of fuel cell systems increased. At the system level, different layouts have been evaluated at the steady-state and by dynamic simulations. Results showed that increasing the operation temperature and pressure improves the overall performance, while changes of the inlet gas compositions improve fuel cell performance.
Źródło:
Chemical and Process Engineering; 2018, 39, 4; 377--393
0208-6425
2300-1925
Pojawia się w:
Chemical and Process Engineering
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
Aerodynamic performance of a new double-flap wing sail
Autorzy:
Li, Dongqin
Zhang, Yili
Li, Peng
Dai, Jingjing
Li, Guohuan
Powiązania:
https://bibliotekanauki.pl/articles/260534.pdf
Data publikacji:
2019
Wydawca:
Politechnika Gdańska. Wydział Inżynierii Mechanicznej i Okrętownictwa
Tematy:
double-flap wing sail
aerodynamic performance
Computational Fluid Dynamics (CFD)
parameter optimization
Opis:
As a type of natural energy resource, wind power is used in the modern implementation of wind-assisted technologies as a method for reducing the fuel consumption and environmental pollution of ocean-going ships. In order to promote the full usage of ocean wind energy for cargo ships, an innovative type of ship propulsion-assisted wing sail is proposed in this paper. The propulsion efficiency of this new wing sail can be increased by enlarging its area in both the transverse and vertical directions in good weather conditions, and it can be folded up automatically in poor weather conditions, improving the sailing safety of the ship. The sail parameters relating to the gaps and rotation angles between different parts of the wing sail are compared, and the values giving the best aerodynamic performance are identified using CFD simulation technology. The results for the lift and drag coefficients for the new wing sail at different attack angles are also compared with those of traditional aerofoil sails, including an arc-shaped rigid sail and a variable-camber sail proposed in 2015. From the viewpoint of the sailing performance of the vessel, our results demonstrate that this new type of wing sail has good aerodynamic performance and can reduce fuel costs for commercial vessels.
Źródło:
Polish Maritime Research; 2019, 4; 61-68
1233-2585
Pojawia się w:
Polish Maritime Research
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
Aerodynamika autobusu miejskiego w ujęciu CFD
Commercial Bus Aerodynamics in Terms of CFD Analysis
Autorzy:
Paszko, M.
Powiązania:
https://bibliotekanauki.pl/articles/311672.pdf
Data publikacji:
2016
Wydawca:
Instytut Naukowo-Wydawniczy "SPATIUM"
Tematy:
autobus miejski
aerodynamika nadwozia typowego
metoda CFD
bus
aerodynamics typical body
CFD method
computational fluid dynamics (CFD)
Opis:
W niniejszym artykule przedstawiono możliwości wykorzystania metod CFD (Computational Fluid Dynamics) w procesie badania aerodynamiki nadwozia typowego, współczesnego autobusu miejskiego. Przedstawiono również proces budowy przestrzennego, numerycznego modelu procesów aerodynamicznych przebiegających w trakcie opływu nadwodzia autobusu miejskiego na przykładzie pakietu Ansys Workbench.
Paper discussed the general usability of the Computional Fluid Dynamics (CFD) in process of studying aerodynamics of the commercial busses.
Źródło:
Autobusy : technika, eksploatacja, systemy transportowe; 2016, 17, 6; 1071-1073
1509-5878
2450-7725
Pojawia się w:
Autobusy : technika, eksploatacja, systemy transportowe
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
Air flow analysis around the autogyro fuselage
Analiza przepływu powietrza wokół kadłuba wiatrakowca
Autorzy:
Czyż, Z.
Ilhan, I.
Akcay, M.
Czarnigowski, J.
Powiązania:
https://bibliotekanauki.pl/articles/101828.pdf
Data publikacji:
2017
Wydawca:
Politechnika Lubelska. Polskie Towarzystwo Promocji Wiedzy
Tematy:
CFD
Computational Fluid Dynamics
gyroplane
aerodynamics
lift force
drag force
obliczeniowa mechanika płynów
wiatrakowiec
aerodynamika
siła nośna
siła oporu
Opis:
The paper presents the results of the simulation of the air flow around the gyroplane without the influence of the rotor and pusher propellers. Three-dimensional calculations were performed using ANSYS Fluent software. Based on the calculations, the values of the drag force and the lift force on each component of the rotorcraft were determined. Based on the results obtained, the effect of angle of attack on the aerodynamic forces was obtained.
W pracy przedstawiono wyniki symulacji opływu modelu wiatrakowca bez wpływu wirnika nośnego oraz śmigła pchającego. Trójwymiarowe obliczenia wykonano za pomocą programu ANSYS Fluent. Na podstawie przeprowadzonych obliczeń wyznaczono wartości siły oporu oraz siły nośnej działające na poszczególne części składowe statku powietrznego. W oparciu o uzyskane wyniki otrzymano wpływ kąta natarcia na siły aerodynamiczne.
Źródło:
Journal of Technology and Exploitation in Mechanical Engineering; 2017, 3, 1; 13-20
2451-148X
Pojawia się w:
Journal of Technology and Exploitation in Mechanical Engineering
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
An estimation of conditions inside construction works during a fire with the use of Computational Fluid Dynamics
Autorzy:
Sztarbała, G.
Powiązania:
https://bibliotekanauki.pl/articles/201986.pdf
Data publikacji:
2013
Wydawca:
Polska Akademia Nauk. Czytelnia Czasopism PAN
Tematy:
computational fluid dynamics (CFD)
fire
buildings
ventilation systems
Opis:
The aim of this paper is to present the application of Computational Fluid Dynamics (CFD) to the assessment of conditions inside construction works during a fire. The CFD method is now commonly used to support the design process of fire safety in construction works. This method is very useful at the preliminary stage of design because it is possible to check the internal environment during a fire and evaluate whether requirements of fire safety are met.
Źródło:
Bulletin of the Polish Academy of Sciences. Technical Sciences; 2013, 61, 1; 155-160
0239-7528
Pojawia się w:
Bulletin of the Polish Academy of Sciences. Technical Sciences
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
An evaluation of turbulence model for vortex breakdown detection over delta wing
Autorzy:
Wibowo, S. B.
Sutrisno, -
Rohmat, T. A.
Powiązania:
https://bibliotekanauki.pl/articles/949942.pdf
Data publikacji:
2018
Wydawca:
Polska Akademia Nauk. Czytelnia Czasopism PAN
Tematy:
turbulence models
vortex breakdown
delta wing
vortex core
computational fluid dynamics
CFD
roll-up vortex
modele turbulencji
awaria wirowa
skrzydło delta
rdzeń vortex
obliczeniowa mechanika płynów
wir zawijający
Opis:
An important phenomenon of delta wing is the mechanism of vortex core, which indicates the increase in lifting force until the occurrence of the vortex breakdown. The computational fluid dynamics (CFD) is very helpful in visualizing and providing analysis of the detailed data. The use of turbulent models will affect the quality of results in obtaining the vortex breakdown phenomenon. This study used several models of turbulence to capture the occurrence of vortex breakdown and compare it with experiments using water tunnel test facility. The results show that all turbulence models give good results at a low angle of attack (AoA), but at a high AoA the DES model gives the results closest to experimental ones with Cl error value of about 1 %. Taking into account the time required and the acceptable level of accuracy, the use of SST and k-ω models is an alternative option for use in the detection of vortex breakdown.
Źródło:
Archive of Mechanical Engineering; 2018, LXV, 3; 399-415
0004-0738
Pojawia się w:
Archive of Mechanical Engineering
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
An example of the use of computational-fluid-dynamics analysis for simulation of two-phase flow in a cyclone with a tangential inlet
Autorzy:
Wójtowicz, R.
Wolak, P.
Powiązania:
https://bibliotekanauki.pl/articles/207368.pdf
Data publikacji:
2016
Wydawca:
Politechnika Wrocławska. Oficyna Wydawnicza Politechniki Wrocławskiej
Tematy:
tangential inlet
CFD
computational fluid dynamics
cyclone
wlot styczny
obliczeniowa mechanika płynów
cyklon
Opis:
The feasibility of using a software package, based on computational fluid dynamics (CFD) codes to simulate two-phase (gas–solid) flows in a cyclone with a tangential inlet was studied. The method-ology of numerical simulations and calculations has been presented and the main parameters influencing the effectiveness of the cyclone elaborated. Findings are presented as contour maps of the distribution of selected flow parameters (velocity, pressure) in some parts of the apparatus or as visualizations of vortex formation structures and particle motion trajectories in the cyclone. The results of simulation were compared with those based on literature correlations and experimental results of laboratory tests.
Źródło:
Environment Protection Engineering; 2016, 42, 3; 109-123
0324-8828
Pojawia się w:
Environment Protection Engineering
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
Analiza charakterystyk aerodynamicznych samolotów klasy uav z wykorzystaniem programu tornado
Analysis of aerodynamic characteristics of UAV aircraft with the use of Tornado software
Autorzy:
Lichoń, D.
Powiązania:
https://bibliotekanauki.pl/articles/313936.pdf
Data publikacji:
2016
Wydawca:
Instytut Naukowo-Wydawniczy "SPATIUM"
Tematy:
BSP
bezzałogowy statek powietrzny
metoda panelowa
metoda CFD
program Tornado
unmanned aerial vehicles
UAV
vortex lattice method
VLM
computational fluid dynamics
CFD
Tornado software
Opis:
W pracy przedstawiono obliczenia charakterystyk aerodynamicznych lekkich samolotów kategorii bezzałogowy statek powietrzny (BSP, ang. UAV - Unmanned Aerial Vehicle). Wykorzystaną metodą obliczeń jest metoda panelowa (ang. VLM – Vortex Lattice Method) wraz z jej praktyczną realizacją w programie Tornado. Jako podstawę weryfikacji poprawności obliczeń przyjęto wyniki tunelowych badań eksperymentalnych wybranych samolotów. Metoda panelowa, obok metody CFD (ang. Computational Fluid Dynamics), jest jedną z metod wykorzystywanych w lotnictwie, w numerycznych obliczeniach przepływów. Cechą charakterystyczną metody panelowej jest rozwiązywanie przepływów potencjalnych. Ogranicza to jej zastosowanie do użytkowego zakresu kątów natarcia skrzydła samolotu, bez możliwości modelowania i analizy oderwania strug powietrza. Do zalet wymienionej metody zaliczamy szybkość wykonywanych obliczeń oraz stosunkowo łatwą do opanowania teorię i implementację numeryczną. Program Tornado jest dopracowanym, dostępnym bezpłatnie narzędziem dedykowanym do obliczeń charakterystyk aerodynamicznych samolotów metodą panelową. Dzięki implementacji w środowisku MatLab, dostęp do kodu źródłowego w postaci plików *.m jest bezpośredni. Cechy te czynią go potencjalnie użytecznym w projektowaniu lekkich samolotów bezzałogowych. Samoloty tej klasy są często konstrukcjami, powstającymi w warunkach ograniczonego zaplecza badawczego i finansowego. Celem niniejszej pracy jest przedstawienie możliwości obliczeniowych programu Tornado, jego ograniczeń, napotkanych problemów i doświadczeń w modelowaniu lekkich samolotów bezzałogowych.
The paper contains analysis of aerodynamic characteristics of UAV with the use of Tornado software. The aim of work is to investigate the usefulness the software in the design of UAV aircraft. The calculated aerodynamic characteristics of selected models were compared with available aerodynamic experimental data. The publication presents also range of calculated aerodynamic data and experiences in aircraft geometry modeling which allows to avoid errors in numerical calculations.
Źródło:
Autobusy : technika, eksploatacja, systemy transportowe; 2016, 17, 12; 1133-1138
1509-5878
2450-7725
Pojawia się w:
Autobusy : technika, eksploatacja, systemy transportowe
Dostawca treści:
Biblioteka Nauki
Artykuł

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