Informacja

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

English (EN)·Polski (PL)·Yкраїнський (UK)
Przejdź do strony domowej biblioteki Centralna Biblioteka Wojskowa Link otwiera się w nowym oknie Logo biblioteki Prolib Integro - strona głównaCentralna Biblioteka Wojskowa

Wyszukujesz frazę "Numerical Simulations" wg kryterium: Temat

  Lista filtrów
Wyrównaj
    Wyświetlanie 1-9 z 9
    Tytuł:
    Numerical methods for fast magnetoacoustic waves in solar coronal loops
    Autorzy:
    Gruszecki, M.
    Murawski, K.
    Powiązania:
    https://bibliotekanauki.pl/articles/1943226.pdf
    Data publikacji:
    2009
    Wydawca:
    Politechnika Gdańska
    Tematy:
    numerical simulations
    Godunov methods
    magnetohydrodynamics
    Opis:
    Numerical methods for standing fast magnetoacoustic kink waves in an isothermal solar coronal slab with a field aligned flow are considered. Such waves are triggered impulsively by a velocity pulse that is initially launched in an ambient medium. The spatial and temporal signatures of these waves are determined by solving two-dimensional, ideal magnetohydrodynamic equations numerically. The Ramses code which resolves complex spatial structures by adopting an adaptive mesh refinement technique and shock-capturing capabilities is used. The numerical results show that spatial and temporal wave signatures are reminiscent to the recent observational findings.
    Źródło:
    TASK Quarterly. Scientific Bulletin of Academic Computer Centre in Gdansk; 2009, 13, 1-2; 75-81
    1428-6394
    Pojawia się w:
    TASK Quarterly. Scientific Bulletin of Academic Computer Centre in Gdansk
    Dostawca treści:
    Biblioteka Nauki
    Artykuł
    Tytuł:
    Analysis of flowing fluid effect on flow averaging tube
    Autorzy:
    Kabaciński, M.
    Lachowicz, C.
    Pospolita, J.
    Powiązania:
    https://bibliotekanauki.pl/articles/1943247.pdf
    Data publikacji:
    2008
    Wydawca:
    Politechnika Gdańska
    Tematy:
    flow averaging tubes
    numerical simulations
    flow measurements
    Opis:
    This paper presents a mathematical model and results of numerical simulations for a fluid flow around a flow averaging tube. The calculations have been performed using the commercially available FLUENT software. The authors have applied the currently known studies of the models of turbulence and their applicability in certain flow conditions and hence selected the RNG k-epsylon turbulence model including appropriate functions to be used for determination of pressures and velocities at the sites of occurrence of considerable gradients. The distributions of pressures and velocities around a sensor are presented along with pressure distributions, instantaneous and averaged in time, on the measuring tube surface. The paper determines the frequencies of measuring tube free vibrations for one sided and two-sided tube fitting for the tube length in the range 100–1500mm. This analysis has been conducted with the aid of solving equations for free undamped vibrations for specific models. The graphical presentation involves an admissible range of tube lengths with one and two-sided fitting for the specified flowing air velocities.
    Źródło:
    TASK Quarterly. Scientific Bulletin of Academic Computer Centre in Gdansk; 2008, 12, 3-4; 217-226
    1428-6394
    Pojawia się w:
    TASK Quarterly. Scientific Bulletin of Academic Computer Centre in Gdansk
    Dostawca treści:
    Biblioteka Nauki
    Artykuł
    Tytuł:
    Absolute instability of compressible three-dimensional flow
    Autorzy:
    Tuliszka-Sznitko, E.
    Powiązania:
    https://bibliotekanauki.pl/articles/1954544.pdf
    Data publikacji:
    1999
    Wydawca:
    Politechnika Gdańska
    Tematy:
    numerical simulations
    compressible flow
    instabilities
    absolute instability
    Opis:
    In the present paper the instability character (absolute/convective) of compressible viscous flow around geometries rotating in uniform flow is analysed. The linear local stability theory is used to investigate the boundary layer stability. Following the works of Briggs and Bers in the field of plasma physics, the absolute instability region is identified by singularities of dispersion relation called pinch - points. Calculations have been made for different Mach numbers and wall temperatures.
    Źródło:
    TASK Quarterly. Scientific Bulletin of Academic Computer Centre in Gdansk; 1999, 3, 1; 5-16
    1428-6394
    Pojawia się w:
    TASK Quarterly. Scientific Bulletin of Academic Computer Centre in Gdansk
    Dostawca treści:
    Biblioteka Nauki
    Artykuł
    Tytuł:
    Godunov-type numerical methods for one- and two-component magnetohydrodynamic equations
    Autorzy:
    Murawski, K.
    Powiązania:
    https://bibliotekanauki.pl/articles/1943228.pdf
    Data publikacji:
    2009
    Wydawca:
    Politechnika Gdańska
    Tematy:
    numerical simulations of hyperbolic equations
    Godunov methods
    magnetohydrodynamics
    Opis:
    In this paper we review Godunov-type numerical methods for one- and two-component magnetohydrodynamic equations. Solving these equations numerically is a formidable task as a result of the internal complexity of these equations and the requirements of [delta] B=0. We present several results of advanced numerical simulations for complex systems. These results prove that the numerical codes which are based on Godunov-type methods, cope with all problems very well.
    Źródło:
    TASK Quarterly. Scientific Bulletin of Academic Computer Centre in Gdansk; 2009, 13, 1-2; 45-73
    1428-6394
    Pojawia się w:
    TASK Quarterly. Scientific Bulletin of Academic Computer Centre in Gdansk
    Dostawca treści:
    Biblioteka Nauki
    Artykuł
    Tytuł:
    The analysis of separation and methods of three-dimensional flow structure detection in the boundary layer shock wave interaction
    Autorzy:
    Czerwińska, J.
    Powiązania:
    https://bibliotekanauki.pl/articles/1954539.pdf
    Data publikacji:
    1999
    Wydawca:
    Politechnika Gdańska
    Tematy:
    shock wave boundary layer interaction
    flow separation
    3D flow structures
    numerical simulations
    Opis:
    The normal shock wave turbulent boundary layer interaction still draws a great deal of attention as a flow phenomenon. This is due to its profound importance to numerous applications. The understanding of phenomena is crucial for future aims connected with the interaction control. Experimental investigations of the interaction have been carried out since the 1940s. They were aimed however at the determination of such general flow features as: pressure distribution, shock wave configuration or oil visualization of separation structures. In order to better understand the phenomenon, measurements of the entire field are required. At present, such measurements do not exist. A great help is expected from numerical simulations in this respect. There is enough experimental data to check the general features of the flow obtained from calculations. This thesis presents numerical simulations of flow that is assumed: steady, three-dimensional, compressible, viscous and turbulent. Its general aim is to present to what extend the modern numerical methods are able to predict the flow in shock wave turbulent boundary layer interaction including shock induced separation structures. These structures are very sensitive to channel geometry and may be useful in the understanding of separation's development. In order to illustrate the abilities of numerical simulations, one aim of the presented thesis is to investigate the effect of the span-wise depth of the nominally two-dimensional test section. The presented results cast some light on the common problems experienced by typical comparisons of two-dimensional simulations to wind tunnel tests having a three-dimensional nature. The first Chapter presents the basic theory of elementary structures. Considerations of elementary structures of the flow along with their dependencies are necessary for a better understanding of the separation flow structures induced by the boundary layer shock wave interaction. The classification of elementary structures will be presented. In addition, the possible occurrence of bifurcation will also be studied. The second Chapter will be devoted to studying specific cases of transonic turbulent flow. The analysis of numerical results will be bounded to the shock wave structure. Studies shall include: the influence of the numerical scheme, three-dimensional effects connected with the changing width of the channel, a comparison to experiment and the influence of the symmetric boundary condition on the flow prediction in the channel. Finally, the boundary layer influence on the 1-foot structure will also be presented. Chapter three will present the separation structures. Here too a comparison to experiments will be done. Changes in separation structures connected with the width of the channel will be studied. The influence of the symmetry boundary condition will be shown. Finally, the specification of the basic flow structures will be done.
    Źródło:
    TASK Quarterly. Scientific Bulletin of Academic Computer Centre in Gdansk; 1999, 3, 1; 53-140
    1428-6394
    Pojawia się w:
    TASK Quarterly. Scientific Bulletin of Academic Computer Centre in Gdansk
    Dostawca treści:
    Biblioteka Nauki
    Artykuł
    Tytuł:
    A parallel adaptive code for compressible Navier-Stokes simulations
    Autorzy:
    Banaś, K.
    Powiązania:
    https://bibliotekanauki.pl/articles/1954541.pdf
    Data publikacji:
    1999
    Wydawca:
    Politechnika Gdańska
    Tematy:
    numerical simulations
    compressible flow
    Navier-Stokes solver
    finite element method
    parallel computing
    adaptive meshes
    Opis:
    The paper presents a finite element code for compressible flow simulations. The code has two important features: adaptivity to increase accuracy of computations by selectively refining a finite element mesh and efficient parallel performance due to a special implementation based on concept of patches of elements. The algorithm for approximating the compressible Navier-Stokes equations is a version of the stabilized finite element method. Three time integration strategies are implemented, explicit, linear implicit and nonlinear implicit, and the GMRES method is used to solve systems of linear equations. For parallel simulations the code uses a special algorithm for mesh partition. The performance of the code is tested for two examples of supersonic flows: one inviscid and one viscous.
    Źródło:
    TASK Quarterly. Scientific Bulletin of Academic Computer Centre in Gdansk; 1999, 3, 1; 17-37
    1428-6394
    Pojawia się w:
    TASK Quarterly. Scientific Bulletin of Academic Computer Centre in Gdansk
    Dostawca treści:
    Biblioteka Nauki
    Artykuł
    Tytuł:
    Multiblock parallel computation of an incompressible 3D flow in turbomachines
    Autorzy:
    Papierski, A.
    Rabiega, M.
    Powiązania:
    https://bibliotekanauki.pl/articles/1954540.pdf
    Data publikacji:
    1999
    Wydawca:
    Politechnika Gdańska
    Tematy:
    numerical simulations
    turbomachinery
    incompressible flow
    3D Navier-Stockes solver
    Navier-Stokes solver
    parallel computing
    Opis:
    A finite volume numerical method for the prediction of a fluid flow in complex geometries such as turbomachinery channels has been parallelized using a domain decomposition approach. A mathematical formulation of a 3-D incompressible steady flow has been presented on the basis of the N-S equations in a grid-oriented co-ordinate system with contravariant velocity components. A parallelized pressure-based implicit algorithm with discretization on a staggered grid has been developed. A message exchange system with a boundary exchange, developed by the authors, has been described. Exemplary calculations have been carried out for a laminar flow through a curved duct and for an inviscid flow through a stage of the centrifugal pump. A good agreement has been obtained in both the cases. Despite considerable simplification that has been introduced in the flow through the pump stage, the computations have shown nearly the same pressure rise in the stage as the measurements. Further directions of numerical investigations of a flow through turbomachines, including in particular those devoted to pressure losses related to the rotor-stator interaction, have been mentioned.
    Źródło:
    TASK Quarterly. Scientific Bulletin of Academic Computer Centre in Gdansk; 1999, 3, 1; 39-52
    1428-6394
    Pojawia się w:
    TASK Quarterly. Scientific Bulletin of Academic Computer Centre in Gdansk
    Dostawca treści:
    Biblioteka Nauki
    Artykuł
    Tytuł:
    Numerical simulations of the effect of time-dependent random mass density field on frequencies of sound waves
    Autorzy:
    Murawski, K.
    Powiązania:
    https://bibliotekanauki.pl/articles/1955804.pdf
    Data publikacji:
    2001
    Wydawca:
    Politechnika Gdańska
    Tematy:
    numerical simulations
    convection - Sun
    oscillations - turbulence
    time-dependent random mass density field
    space-dependent random field
    Opis:
    Numerical simulations of the effect of random mass density field on frequencies of sound waves are considered for driven and impulsive sound waves which are described by one-dimensional hydrodynamic equations, with the ponderomotive force which depends stochastically both on space and time. The numerical results reveal frequency increase for short waves and both wave damping and amplification for the overall range of wavenumbers. Moreover, a space- and time-dependent random field leads to a generation of a wide frequency spectrum which contains both retarded and speeded up waves.
    Źródło:
    TASK Quarterly. Scientific Bulletin of Academic Computer Centre in Gdansk; 2001, 5, 2; 229-238
    1428-6394
    Pojawia się w:
    TASK Quarterly. Scientific Bulletin of Academic Computer Centre in Gdansk
    Dostawca treści:
    Biblioteka Nauki
    Artykuł
    Tytuł:
    FE-simulations of rapid silo flow with a polar elasto-plastic constitutive model
    Autorzy:
    Tejchman, J.
    Powiązania:
    https://bibliotekanauki.pl/articles/1953957.pdf
    Data publikacji:
    1998
    Wydawca:
    Politechnika Gdańska
    Tematy:
    finite element simulations
    polar elasto-plastic constitutive model
    silo flow
    numerical modelling
    model silo
    convergent smooth walls
    Opis:
    The paper presents results on numerical modelling of rapid flow of granular materials in a model silo with convergent smooth walls. The calculations were performed with a finite element method based on a polar elasto-plastic constitutive relation by Muhlhaus (1995). The relation differs from the conventional theory of plasticity by the presence of Cosserat rotations and couple stresses using a mean grain diameter as a characteristic length. The characteristic length causes that numerical results do not depend upon the mesh discretisation. The model tests on rapid silo flow of glass beads performed by Renner in a glass hopper with a large wall inclination from the bottom were numerically simulated. The plane strain FE-calculations were performed by taking into account inertial forces and linear viscous damping. A satisfactory agreement between numerical and experimental results was obtained. Advantages and limitations of a continuum approach for simulations of rapid silo flow were outlined.
    Źródło:
    TASK Quarterly. Scientific Bulletin of Academic Computer Centre in Gdansk; 1998, 2, 3; 473-501
    1428-6394
    Pojawia się w:
    TASK Quarterly. Scientific Bulletin of Academic Computer Centre in Gdansk
    Dostawca treści:
    Biblioteka Nauki
    Artykuł
      Wyświetlanie 1-9 z 9

      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