Informacja

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

Wyszukujesz frazę "CFD" wg kryterium: Temat


Tytuł:
Application of CFD for analysis of the ship and propeller flow
Autorzy:
Bugalski, T. J.
Szantyr, J.
Powiązania:
https://bibliotekanauki.pl/articles/1953974.pdf
Data publikacji:
1998
Wydawca:
Politechnika Gdańska
Tematy:
computational fluid dynamics CFD
CFD
propeller flow
ships
Navier-Stokes equation
free surface
propeller operation
PANSHIP computer system
Opis:
The paper describes the computer system PANSHIP for analysis of flow around the ship hull moving with constant velocity in calm water, including the effects of free surface and propeller operation. This system calculates the potential flow using the discrete distribution of Rankine sources on the hull. Viscous flow is computed using the integral method in the bow section and Reynolds averaged Navier Stokes equation (RANS) in the stern section of the ship hull. Results of this analysis may be directly used in ship hull design and they may also serve as input for calculation of the unsteady flow phenomena accompanying propeller operation in the non-uniform velocity field generated by the hull. PANSHIP has been verified experimentally and it forms a useful tool available for ship designers and for marine hydrodynamicists.
Źródło:
TASK Quarterly. Scientific Bulletin of Academic Computer Centre in Gdansk; 1998, 2, 2; 349-356
1428-6394
Pojawia się w:
TASK Quarterly. Scientific Bulletin of Academic Computer Centre in Gdansk
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
Computational fluid dynamics methods in turbomachinery
Autorzy:
Chmielniak, T. J.
Powiązania:
https://bibliotekanauki.pl/articles/1953985.pdf
Data publikacji:
1998
Wydawca:
Politechnika Gdańska
Tematy:
computational fluid dynamics CFD
CFD
turbomachinery
numerical methods
modelling
steady flow
unsteady flow
multiphase flow
multicomponent flow
blade cooling
Opis:
This paper aims to present a general view of flow problems in turbomachinery and the current levels of numerical methods for solving these problems. The flow models used for modelling phenomena in blade cascades are presented. Models of turbulence are discussed. A variety of examples of turbomachinery problems, such as steady, unsteady, multiphase and multicomponent flows, and also blade cooling are described. The actual research fields of computational fluid mechanics are presented.
Źródło:
TASK Quarterly. Scientific Bulletin of Academic Computer Centre in Gdansk; 1998, 2, 2; 205-213
1428-6394
Pojawia się w:
TASK Quarterly. Scientific Bulletin of Academic Computer Centre in Gdansk
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
Numerical simulation of 3D flow in axial turbomachines
Autorzy:
Yershov, S.
Rusanov, A. V.
Gardzielewicz, A.
Lampart, P.
Świrdyczuk, J.
Powiązania:
https://bibliotekanauki.pl/articles/1953978.pdf
Data publikacji:
1998
Wydawca:
Politechnika Gdańska
Tematy:
numerical simulation
axial turbomachines
3D flow
3D viscous compressible flow
Navier-Stokes equation
ENO reconstruction
computational efficiency
computational fluid dynamics CFD
Godunov-type upwind differencing
Opis:
The paper is intended to describe a method for the calculation of 3D viscous compressible (subsonic or supersonic) flow in axial turbomachines described in the form of thin-layer Reynolds-averaged Navier-Stokes equations. The method draws on Godunov-type upwind differencing and ENO reconstruction suggested by Harten (1987), so as to assure monotonicity preservation and high accuracy of computational results. The computational efficiency is achieved thanks to the implementation of a simplified H-type multi-grid approach and delta -form implicit step. Turbulent effects are simulated with the help of a modified algebraic model of Baldwin-Lomax (1978). This method was at the foundation of a computer code-a complex software package to calculate 3D flow in multi-stage turbomachines that allows us to obtain local characteristics, like temperature, pressure, density or velocity distributions, as well as global characteristics, such as flow rates, stage reaction, flow efficiency for the considered turbine/compressor stage. The paper also gives selected results of computation of a number of turbomachinery cascades, showing that these results agree reasonably well with the available experimental data.
Źródło:
TASK Quarterly. Scientific Bulletin of Academic Computer Centre in Gdansk; 1998, 2, 2; 319-347
1428-6394
Pojawia się w:
TASK Quarterly. Scientific Bulletin of Academic Computer Centre in Gdansk
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
Short review of the CFD activities in Poland
Autorzy:
Kazimierski, Z.
Powiązania:
https://bibliotekanauki.pl/articles/1953991.pdf
Data publikacji:
1998
Wydawca:
Politechnika Gdańska
Tematy:
computational fluid dynamics CFD
CFD activities
universities
scientific centres
Opis:
Computational fluid dynamics is being developed at several universities and scientific centres in Poland. These centres are considered and a general description of CFD activities is provided. It should be emphasised that the centres mentioned are only the best known ones. The information provided has been prepared in co-operation with the responsible scientists and is authorised by them. Therefore the form of topics description is not uniform.
Źródło:
TASK Quarterly. Scientific Bulletin of Academic Computer Centre in Gdansk; 1998, 2, 2; 199-204
1428-6394
Pojawia się w:
TASK Quarterly. Scientific Bulletin of Academic Computer Centre in Gdansk
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
Transonic flows, shock wave-turbulent boundary layer interaction
Autorzy:
Doerffer, P.
Kaczyński, J.
Powiązania:
https://bibliotekanauki.pl/articles/1953982.pdf
Data publikacji:
1998
Wydawca:
Politechnika Gdańska
Tematy:
transonic flows
shock waves
turbulent boundary layer interaction
computational fluid dynamics CFD
CFD
flow configurations
profile flow
helicopter rotor
hovering
forward flight
internal flows
Opis:
Shock wave-boundary layer interaction is one of the most important phenomenon in transonic flows. Due to its complexity it is difficult as well for experimental as for numerical study. The growing potential of CFD is therefore of great importance. Different aspects of shock wave-boundary layer interaction should be studied in different flow configurations. Therefore results concerning profile flow, helicopter rotor at hovering and forward flight and internal flows are presented in this paper. These are to illustrate our ability in CFD in general. Besides flow simulation the development of codes is carried out.
Źródło:
TASK Quarterly. Scientific Bulletin of Academic Computer Centre in Gdansk; 1998, 2, 2; 271-286
1428-6394
Pojawia się w:
TASK Quarterly. Scientific Bulletin of Academic Computer Centre in Gdansk
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
Pseudospectral approximation compared with control volume formulation and finite differences- some test cases
Autorzy:
Tyliszczak, A.
Bogusławski, A.
Powiązania:
https://bibliotekanauki.pl/articles/1953944.pdf
Data publikacji:
2000
Wydawca:
Politechnika Gdańska
Tematy:
computational fluid dynamics CFD
CFD
spectral methods
pseudospectral method
supersonic flows
driven cavity
Opis:
The paper presents comparison of the pseudospectral method with low-order approximation for two test cases. The first test case is quasi one-dimensional supersonic flow through converging-diverging nozzle for which exact solution exists. The comparison of the error of pseudospectral approximation and upwind finite-differences using Steger-Warming flux splitting method shows high accuracy of the pseudospectral method even for few collocation points. The same conclusion is formulated for the second test case, namely incompressible flow in two-dimensional driven cavity solved by control volume formulation with modified QUICK upwinding scheme and SIMPLEC algorithm for pressure correction. As usually conclusions concerning accuracy of numerical methods are flow case dependent, but the two examples shown give some idea about the accuracy and resolution of spectral approximation versus standard CFD schemes.
Źródło:
TASK Quarterly. Scientific Bulletin of Academic Computer Centre in Gdansk; 2000, 4, 2; 193-202
1428-6394
Pojawia się w:
TASK Quarterly. Scientific Bulletin of Academic Computer Centre in Gdansk
Dostawca treści:
Biblioteka Nauki
Artykuł
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:
Applicability of flow simulation models to the case of radial inflow onto a rotating core
Autorzy:
Biernacki, R.
Powiązania:
https://bibliotekanauki.pl/articles/1955813.pdf
Data publikacji:
2001
Wydawca:
Politechnika Gdańska
Tematy:
turbulent flow
numerical flow simulation
flow simulation models
steam turbines
turbine inlet
computational fluid dynamics CFD
Opis:
The paper presents the results of fluid flow simulations carried out by means of the FIDAP7.6 program (a fluid dynamics FEM package) for the case of radial inflow onto a rotating shaft. The particular geometric configuration has been chosen to resemble a generalized inlet chamber of twin low-pressure steam turbines, but with the axial outlet section extended to allow better observation of flow instabilities in that region. The calculations were carried out for the same channel geometry for both compressible and incompressible flow, using the same or slightly varying boundary conditions. Extensive variation in non-physical parameters of the model was explored, such as applying different meshes over the region, as well as utilizing different turbulence and upwinding models. The intent of this research was to evaluate the relative applicability of the various available flow models to the simulation of axisymmetric flows with steep velocity gradients, and to discover the limitations of these models. The calculations have in fact established significant differences in the behavior of the simulated flow for the different meshes and models. Some results were characterized by extensive areas of recirculating flow whereas others, for the same boundary conditions, showed no recirculation. Correct near-wall meshing as well as the choice of the upwinding scheme were established as the critical factors in this regard. There was also noticeable variation in outlet velocity profiles. An extensive zone of separation within the investigated channel as well as a standing annular vortex near the point of stagnation are flow features of some interest. These patterns of flow change in response to the changing non-physical parameters; the separation zone in particular is absent or slow to develop under some setups. The influence of inflow parameters, the initial velocity distribution and turbulent intensity in particular, on flow behavior in contact with the rotating shaft have also been an area of investigation, as these are often defined with considerable uncertainty in practical applications. It was observed that some latitude in assuming these parameters did not significantly alter the relevant flow parameters at outlet (the velocity and pressure distributions), although it did induce variation in other aspects of the flow (such as the extent of the standing vortex).
Źródło:
TASK Quarterly. Scientific Bulletin of Academic Computer Centre in Gdansk; 2001, 5, 2; 141-154
1428-6394
Pojawia się w:
TASK Quarterly. Scientific Bulletin of Academic Computer Centre in Gdansk
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
Flameless oxidation at the GT26 gas turbine: numerical study via full chemistry
Autorzy:
Ochrymiuk, T.
Badur, J.
Powiązania:
https://bibliotekanauki.pl/articles/1955802.pdf
Data publikacji:
2001
Wydawca:
Politechnika Gdańska
Tematy:
combustion
full kinetics of chemical reaction
CFD
computational fluid dynamics CFD
flameless oxidation
flameless combustion
Opis:
Sequential combustion was first applied to gas turbines more than 40 years ago, and almost half of these early machines are still operating. This form of oxidation leads to the flame-less combustion at a second chamber. In GT26, the second stage combustor has 24 SEV burners which are similar in action to the well known ABB EV burner. In this paper, a 3D numerical simulation of the first EV combustor and the second SEV-combustor are performed for normal operating conditions (exhaust mass flow 542 kg/s, exhaust temperature 610 C). Physical modelling of the flame-less oxidation is based on an original implementation of the Gri-Mech mechanism (325 chemical reactions) into the Fluent 5.4. Precise estimation of NOx emission and other pollutants has been done.
Źródło:
TASK Quarterly. Scientific Bulletin of Academic Computer Centre in Gdansk; 2001, 5, 2; 239-246
1428-6394
Pojawia się w:
TASK Quarterly. Scientific Bulletin of Academic Computer Centre in Gdansk
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
Numerical investigation of flow in mixed-flow pump with volute
Autorzy:
Sedlar, M.
Powiązania:
https://bibliotekanauki.pl/articles/1967635.pdf
Data publikacji:
2001
Wydawca:
Politechnika Gdańska
Tematy:
CFD
computational fluid dynamics CFD
flow separation
cavitation
Navier-Stokes equation
unsteady phenomena
mixed-flow pump
volute
Opis:
The work considers the modelling of flow in a complete mixed-flow pump with volute, including tip leakage flows, using both quasi-steady and true transient models of rotor/stator interaction. The CFX-TASCflow CFD package from AEA Technology is applied to calculate flows for a wide range of flow rates from about 0.2 to 1.4 Q/sub 0pt/. Fairly detailed flow structures have been predicted based on the flow rates, especially impeller inlet recirculation and separation on the suction side of the blades for suboptimal rates of flow, as well as strong secondary flows and separation in the volute for off-design conditions. The rotor/stator interaction influence on flow phenomena both in the impeller and volute have been investigated with very interesting results, providing good insight into the dynamics of flow close to the volute tongue. Based on the computational results, pump performance curves (Q-H, Q- eta /sub h/ and Q-P, eta /sub h/ being the hydraulic efficiency) have been obtained. The data from this numerical investigation have been used to improve the inlet part of the impeller blades, especially close to the tip. The geometry modifications have resulted in reduced cavitation in the impeller as well as noise at suboptimal rates of flow.
Źródło:
TASK Quarterly. Scientific Bulletin of Academic Computer Centre in Gdansk; 2001, 5, 4; 595-602
1428-6394
Pojawia się w:
TASK Quarterly. Scientific Bulletin of Academic Computer Centre in Gdansk
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
Numerical investigation of the secondary flow development in turbine cascade
Autorzy:
Doerffer, P.
Rachwalski, J.
Magagnato, F.
Powiązania:
https://bibliotekanauki.pl/articles/1955810.pdf
Data publikacji:
2001
Wydawca:
Politechnika Gdańska
Tematy:
turbines
computational fluid dynamics CFD
secondary flow
wind turbines
Opis:
The results represent the first attempt of the numerical analysis of 3-D secondary flows formed in the linear turbine cascade wind tunnel. Numerical simulations were carried out by means of the SPRC code. It was possible to make presented here calculations thanks to the cluster of PC's providing sufficient computational resources. In order to be able to verify the obtained results the case considered is the workshop test case (D.G.Gregory-Smith 1994 Turbomachinery Workshop Test Case No.3 116). It has been shown that the obtained results are in a very good agreement with experiment. It gave confidence in the results and several important conclusions concerning the development of streamwise vortices could be made thanks to the work carried out.
Źródło:
TASK Quarterly. Scientific Bulletin of Academic Computer Centre in Gdansk; 2001, 5, 2; 165-178
1428-6394
Pojawia się w:
TASK Quarterly. Scientific Bulletin of Academic Computer Centre in Gdansk
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
Numerical simulation and theoretical analysis of the 3D viscous flow in centrifugal impellers
Autorzy:
Kang, S.
Hirsch, Ch.
Powiązania:
https://bibliotekanauki.pl/articles/1967654.pdf
Data publikacji:
2001
Wydawca:
Politechnika Gdańska
Tematy:
centrifugal compressor
secondary flow
CFD
computational fluid dynamics CFD
tip leakage flows
Opis:
This paper investigates the three-dimensional viscous ow in centrifugal impellers through theoretical analysis and numerical simulations, which is a summary of the authors' recent work. A quantitative evaluation of the dierent contributions to the streamwise vorticity is performed, namely, the passage vortices along the endwalls due to the ow turning; a passage vortex generated by the Coriolis forces proportional to the local loading and mainly active in the radial parts of the impeller; blade surface vortices due to the meridional curvature. In the numerical simulation the NASA Large Scale Centrifugal Compressor (LSCC) impeller with vaneless diuser is computed at three ow rates. An advanced Navier-Stokes solver, EURANUS/TURBO is applied with an algebraic turbulence model of Badwin-Lomax and a linear k-" model for closure, for dierent meshes. An in-depth validation has been performed based on the measured data. An excellent agreement is obtained for most of the data over a wide region of the ow passage. Structures of the 3D ow in the blade passage and the tip region, and their variations with ow rate as well, are analysed based on the numerical results.
Źródło:
TASK Quarterly. Scientific Bulletin of Academic Computer Centre in Gdansk; 2001, 5, 4; 433-458
1428-6394
Pojawia się w:
TASK Quarterly. Scientific Bulletin of Academic Computer Centre in Gdansk
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
Numerical simulation of 3D viscous turbomachinery flow with high-resolution ENO scheme and modern turbulence model
Autorzy:
Yershov, S. V.
Rusanov, A. V.
Powiązania:
https://bibliotekanauki.pl/articles/1967653.pdf
Data publikacji:
2001
Wydawca:
Politechnika Gdańska
Tematy:
CFD
computational fluid dynamics CFD
turbomachinery
Navier-Stokes equation
turbulence
Opis:
This paper presents the basic principles of construction of numerical models for 3D viscous turbulent flows through multi stage turbomachines. The great attention is given to such properties of the methods as accuracy, linear and non-linear stability, robustness and computational efficiency. It is shown that these properties can be guaranteed if the implicit Godunov’s type ENO scheme is used. A 3D code FLOWER has been developed within this concept. Using the code the numerical results are obtained for flows through high loaded compressor cascades, a turbine stage, a low-pressure multi stage turbine and a centrifugal compressor stage. The results of optimisation of a low-pressure turbine last stage are presented.
Źródło:
TASK Quarterly. Scientific Bulletin of Academic Computer Centre in Gdansk; 2001, 5, 4; 459-476
1428-6394
Pojawia się w:
TASK Quarterly. Scientific Bulletin of Academic Computer Centre in Gdansk
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
Performance prediction of centrifugal pumps with CFD-tools
Autorzy:
Dick, E.
Vierendeels, J.
Serbruyns, S.
Vande Voorde, J.
Powiązania:
https://bibliotekanauki.pl/articles/1967637.pdf
Data publikacji:
2001
Wydawca:
Politechnika Gdańska
Tematy:
centrifugal pumps
CFD analysis
performance prediction
Opis:
The CFD code FLUENT, version 5.4, has been used for the flow analysis of two test pumps of end-suction volute type: one of low specific speed and one of medium specific speed. For both, head as a function of flow rate for constant rotational speed is known from experiments. FLUENT provides three calculation methods for analysis of turbomachinery flows: the multiple reference frame method (MRF), the mixing plane method (MP) and the sliding mesh method (SM). In all three methods, the flow in the rotor is calculated in a rotating reference frame, while the flow in the stator is calculated in an absolute reference frame. In the MRF and MP methods steady flow equations are solved, while in the SM method, unsteady flow equations are solved. The SM method does not introduce physical approximations. The steady methods approximate the unsteady interaction between rotor and stator. The cost of the unsteady method is, however, typically 30 to 50 times higher than the cost of the steady methods. It is found that the MRF and MP methods lead to completely erroneous flow field predictions for flows far away from the best efficiency point. This makes the steady methods useless for general performance prediction.
Źródło:
TASK Quarterly. Scientific Bulletin of Academic Computer Centre in Gdansk; 2001, 5, 4; 579-594
1428-6394
Pojawia się w:
TASK Quarterly. Scientific Bulletin of Academic Computer Centre in Gdansk
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
Prediction of turbomachinery flow physics from CFD - review of recent computations of APPACET test cases
Autorzy:
Gregory-Smith, D. G.
Crossland, S. C.
Powiązania:
https://bibliotekanauki.pl/articles/1967658.pdf
Data publikacji:
2001
Wydawca:
Politechnika Gdańska
Tematy:
turbomachinery
CFD
computational fluid dynamics CFD
turbulence modelling
grid dependence
unsteady interaction
Opis:
In order to maintain a competitive edge, the turbomachinery industry has to rely increasingly on design and analysis methods based on numerical simulation of flow. The European funded APPACET was set up to study the application of turbulence modelling and the simulation of unsteady interactions to provide guidelines for the application of CFD to design. This paper shows the results of computations of four of the test cases studied by the project. The importance of grid refinement has been clearly demonstrated, but no evidence was found that one family of turbulence models could be definitely better than the other. Compared to steady results, unsteady time-averaged solutions have not shown any major improvement in accuracy. However unsteady flow phenomena generating losses within each blade row have been captured and partly explained.
Źródło:
TASK Quarterly. Scientific Bulletin of Academic Computer Centre in Gdansk; 2001, 5, 4; 407-431
1428-6394
Pojawia się w:
TASK Quarterly. Scientific Bulletin of Academic Computer Centre in Gdansk
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