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 "convection" wg kryterium: Wszystkie pola

  Lista filtrów
Wyrównaj
    Wyświetlanie 1-8 z 8
    Tytuł:
    Natural convection from four circular cylinders in across arrangement within horizontal annular space
    Autorzy:
    Laidoudi, Houssem
    Powiązania:
    https://bibliotekanauki.pl/articles/387589.pdf
    Data publikacji:
    2020
    Wydawca:
    Politechnika Białostocka. Oficyna Wydawnicza Politechniki Białostockiej
    Tematy:
    natural convection
    multiple cylinders
    annular space
    heat transfer
    numerical simulation
    Opis:
    Numerical investigation is accomplished to study the roles of governing parameters of natural convection on the fluid motion and heat transfer rate of four heated circular cylinders placed inside a circular enclosure of cold surface. The cylinders are positioned in across arrangement. The representative results are obtained within the ranges of initial conditions as: Prandtl number (Pr = 7.1 to 1000) and Rayleigh number (Ra = 103 to 105). The average Nusselt number of each inner cylinder is computed. The effects of thermal buoyancy strength on the fluid motion and temperature are also illustrated. It was found that the heat transfer rate of cylinders depends significantly on the position inside the enclosure. Moreover, the role of Prandtl number on flow and thermal patterns is negligible. The values of Nusselt number are also given, which can be useful for some engineering applications.
    Źródło:
    Acta Mechanica et Automatica; 2020, 14, 2; 98-102
    1898-4088
    2300-5319
    Pojawia się w:
    Acta Mechanica et Automatica
    Dostawca treści:
    Biblioteka Nauki
    Artykuł
    Tytuł:
    Behaviour of a non-newtonian fluid in a helical tube under the influence of thermal buoyancy
    Autorzy:
    Ramla, Mohamed
    Laidoudi, Houssem
    Bouzit, Mohamed
    Powiązania:
    https://bibliotekanauki.pl/articles/2105993.pdf
    Data publikacji:
    2022
    Wydawca:
    Politechnika Białostocka. Oficyna Wydawnicza Politechniki Białostockiej
    Tematy:
    helical heat exchanger
    mixed convection
    forced convection
    power-law fluids
    Nusselt number
    Opis:
    This work is an evaluative study of heat transfer in the helical-type heat exchanger. The fluid used is non-Newtonian in nature and is defined by Oswald’s model. The work was performed numerically by solving each of the Navier–Stokes equations and the energy equation using the package ANSYS-CFX. Following are the aspects that have been dealt with in this paper: the effects of thermal buoyan-cy, fluid nature and the tube shape on the heat transfer, and the fluid comportment. The interpretation of the obtained results was done by analyzing the isotherms and the streamlines. The mean values of the Nusselt number were also obtained in terms of the studied parame-ters. The results of this research enabled us to arrive at the following conclusion: the intensity of thermal buoyancy and the nature of the fluid affect the heat transfer distribution but keep the overall rate of heat transfer the same.
    Źródło:
    Acta Mechanica et Automatica; 2022, 16, 2; 111--118
    1898-4088
    2300-5319
    Pojawia się w:
    Acta Mechanica et Automatica
    Dostawca treści:
    Biblioteka Nauki
    Artykuł
    Tytuł:
    MHD forced convection using ferrofluid over a backward facing step containing a finned cylinder
    Autorzy:
    Toumi, Meriem
    Bouzit, Mohamed
    Bouzit, Fayçal
    Mokhefi, Abderrahim
    Powiązania:
    https://bibliotekanauki.pl/articles/2106228.pdf
    Data publikacji:
    2022
    Wydawca:
    Politechnika Białostocka. Oficyna Wydawnicza Politechniki Białostockiej
    Tematy:
    fin positions
    forced convection
    nanoparticles
    heat transfer
    finned cylinder
    magnetohydrodynamic
    backward facing step
    Opis:
    In this paper, a numerical study of forced convection on a backward facing step containing a single-finned fixed cylinder has been performed, using a ferrofluid and external magnetic field with different inclinations. The partial differential equations, which determine the conservation equations for mass, momentum and energy, were solved using the finite element scheme based on Galerkin’s method. The analysis of heat transfer characteristics by forced convection was made by taking different values of the Reynolds number (Re between 10 and 100), Hartmann number (Ha between 0 and 100), nanoparticles concentration (φ between 0 and 0.1) and magnetic field inclination (γ between 0° and 90°); also, several fin positions α [0°–180°] were taken in the counter clockwise direction by a step of 5. After analysing the results, we concluded that Hartmann number, nanoparticles concentration, Reynolds number and magnetic field angles have an influence on the heat transfer rate. However, the fin position on the cylinder has a big impact on the Nusselt number and therefore on heat transfer quality. The best position of the fin is at (α = 150°), which gives the best Nusselt number and therefore the best heat trans-fer, but the fin position at (α = 0°) remains an unfavourable case that gives the lowest Nusselt values.
    Źródło:
    Acta Mechanica et Automatica; 2022, 16, 1; 70--81
    1898-4088
    2300-5319
    Pojawia się w:
    Acta Mechanica et Automatica
    Dostawca treści:
    Biblioteka Nauki
    Artykuł
    Tytuł:
    CuO–water mhd mixed convection analysis and entropy generation minimization in double-lid–driven u-shaped enclosure with discrete heating
    Autorzy:
    Mliki, Bouchmel
    Miri, Rached
    Djebali, Ridha
    Abbassi, Mohamed A.
    Powiązania:
    https://bibliotekanauki.pl/articles/2204647.pdf
    Data publikacji:
    2023
    Wydawca:
    Politechnika Białostocka. Oficyna Wydawnicza Politechniki Białostockiej
    Tematy:
    U-shaped enclosure
    MHD mixed convection
    nanoliquids
    double lid-driven cavity
    entropy generation
    LBM
    Opis:
    The present study explores magnetic nanoliquid mixed convection in a double lid–driven U-shaped enclosure with discrete heat-ing using the lattice Boltzmann method (LBM) numerical method. The nanoliquid thermal conductivity and viscosity are calculated using the Maxwell and Brinkman models respectively. Nanoliquid magnetohydrodynamics (MHD) and mixed convection are analyzed and entropy generation minimisation has been studied. The presented results for isotherms, stream isolines and entropy generation describe the interaction between the various physical phenomena inherent to the problem including the buoyancy, magnetic and shear forces. The operating parameters’ ranges are: Reynolds number (Re: 1–100), Hartman number (Ha: 0–80), magnetic field inclination (γ: 0°–90°), nanoparticles volume fraction (ϕ: 0–0.04) and inclination angle (α: 0°–90°). It was found that the and the total entropy generation augment by increasing Re, ϕ: and γ. conversely, an opposite effect was obtained by increasing Ha and α. The optimum magnetic field and cavity inclination angles to maximum heat transfer are γ = 90° and α = 0.
    Źródło:
    Acta Mechanica et Automatica; 2023, 17, 1; 112--123
    1898-4088
    2300-5319
    Pojawia się w:
    Acta Mechanica et Automatica
    Dostawca treści:
    Biblioteka Nauki
    Artykuł
    Tytuł:
    Numerical solution of natural convective heat transfer under magnetic field effect
    Autorzy:
    Şahin, Serpil
    Demir, Hüseyin
    Powiązania:
    https://bibliotekanauki.pl/articles/387646.pdf
    Data publikacji:
    2019
    Wydawca:
    Politechnika Białostocka. Oficyna Wydawnicza Politechniki Białostockiej
    Tematy:
    natural convection heat transfer
    rayleigh number
    chandrasekhar number
    pseudo time derivative
    newtonian fluid
    pseudoplastic fluid
    Opis:
    In this study, non-Newtonian pseudoplastic fluid flow equations for 2-D steady, incompressible, the natural convective heat transfer are solved numerically by pseudo time derivative. The stability properties of natural convective heat transfer in an enclosed cavity region heated from below under magnetic field effect are investigated depending on the Rayleigh and Chandrasekhar numbers. Stability properties are studied, in particular, for the Rayleigh number from 10[indeks górny]4 to 10[indeks górny]6 and for the Chandrasekhar number 3, 5 and 10. As a result, when Rayleigh number is bigger than 10[indeks górny]6 and Chandrasekhar number is bigger than 10, the instability occurs in the flow domain. The results obtained for natural convective heat transfer problem are shown in the figures for Newtonian and pseudoplastic fluids. Finally, the local Nusselt number is evaluated along the bottom wall.
    Źródło:
    Acta Mechanica et Automatica; 2019, 13, 1; 23-29
    1898-4088
    2300-5319
    Pojawia się w:
    Acta Mechanica et Automatica
    Dostawca treści:
    Biblioteka Nauki
    Artykuł
    Tytuł:
    Mechanizmy wymiany ciepła w ośrodku gruntowym
    Heat exchange mechanisms in ground
    Autorzy:
    Biernacka, B.
    Powiązania:
    https://bibliotekanauki.pl/articles/402617.pdf
    Data publikacji:
    2015
    Wydawca:
    Politechnika Białostocka. Oficyna Wydawnicza Politechniki Białostockiej
    Tematy:
    grunt
    przewodzenie ciepła
    przewodność cieplna gruntu
    konwekcja
    temperatura gruntu
    ground
    conduction of heat
    thermal conductivity of soil
    convection
    ground temperature
    Opis:
    W artykule omówiono mechanizmy związane z wymianą ciepła w gruncie. Dominującym sposobem przekazywania ciepła w gruncie jest przewodzenie. Przewodność cieplna gruntu zależy przede wszystkim od rodzaju, porowatości i wilgotności gruntu. W gruncie zachodzi również zjawisko konwekcji swobodnej i wymuszonej.
    The article contains the most important issues connected with heat transfer in the ground. The main form of heat transfer in ground is conduction. Thermal conductivity mainly depends on type of the soil and its porosity and moisture. Inside there are also phenomena called forced and natural convection. The aim of the work is overview and description of heat transfer mechanisms in the ground. Knowledge of thermal phenomena occurring in the ground is necessary to determine the ground temperature field using numerical methods and semi-empirical formulas
    Źródło:
    Budownictwo i Inżynieria Środowiska; 2015, 6, 3; 107-111
    2081-3279
    Pojawia się w:
    Budownictwo i Inżynieria Środowiska
    Dostawca treści:
    Biblioteka Nauki
    Artykuł
    Tytuł:
    Magneto convection in a layer of nanofluid with soret effect
    Autorzy:
    Chand, R.
    Rana, G. C.
    Powiązania:
    https://bibliotekanauki.pl/articles/387119.pdf
    Data publikacji:
    2015
    Wydawca:
    Politechnika Białostocka. Oficyna Wydawnicza Politechniki Białostockiej
    Tematy:
    nanofluid
    Zero-Flux
    Soret Effect
    Nanofluid Lewis Number
    Chandrasekhar Number
    Galerkin methods
    magnetic field
    pole magnatyczne
    metoda Galerkina
    efekt Soreta
    liczba Lewisa
    liczba Chandrasekhara
    nanopłyny
    nanociecze
    Opis:
    Double diffusive convection in a horizontal layer of nanofluid in the presence of uniform vertical magnetic field with Soret effect is investigated for more realistic boundary conditions. The flux of volume fraction of nanoparticles is taken to be zero on the isothermal boundaries. The normal mode method is used to find linear stability analysis for the fluid layer. Oscillatory convection is ruled out because of the absence of the two opposing buoyancy forces. Graphs have been plotted to find the effects of various parameters on the stationary convection and it is found that magnetic field, solutal Rayleigh number and nanofluid Lewis number stabilizes fluid layer, while Soret effect, Lewis number, modified diffusivity ratio and nanoparticle Rayleigh number destabilize the fluid layer.
    Źródło:
    Acta Mechanica et Automatica; 2015, 9, 2; 63-69
    1898-4088
    2300-5319
    Pojawia się w:
    Acta Mechanica et Automatica
    Dostawca treści:
    Biblioteka Nauki
    Artykuł
    Tytuł:
    Soret and dufour effects on chemically reacting and viscous dissipating nanofluid flowing past a moving porous plate in the presence of a heat source/sink
    Autorzy:
    Aastha, Aastha
    Chand, Khem
    Powiązania:
    https://bibliotekanauki.pl/articles/2204618.pdf
    Data publikacji:
    2023
    Wydawca:
    Politechnika Białostocka. Oficyna Wydawnicza Politechniki Białostockiej
    Tematy:
    Soret and Dufour effects
    viscous dissipation
    heat source/sink
    chemically reacting nanofluid
    free convection
    Opis:
    This study performed a numerical investigation of the Soret and Dufour effects on unsteady free convective chemically reacting nanofluid flowing past a vertically moving porous plate in the presence of viscous dissipation and a heat source/sink. The equations direct-ing the flow are non-dimensionalised, modified to ordinary differential equations and emerging equations are resolved computationally by using the bvp4c function in MATLAB software. The results obtained from this analysis indicate that the resulting velocity of the nanofluid increases with increasing Grashof number, mass Grashof number and porosity parameter. An increase in the Dufour number increases the fluid temperature, whereas the concentration profile declines with the increase in the Schmidt number. It is also observed that the skin fric-tion coefficient, Nusselt number and Sherwood number increase with increasing magnetic field parameter, Eckert number and Schmidt number, respectively. The present study reveals the impact of Soret and Dufour effects on heat and mass transfer rates in chemically re-acting and viscous dissipating nanofluids.
    Źródło:
    Acta Mechanica et Automatica; 2023, 17, 2; 263--271
    1898-4088
    2300-5319
    Pojawia się w:
    Acta Mechanica et Automatica
    Dostawca treści:
    Biblioteka Nauki
    Artykuł
      Wyświetlanie 1-8 z 8

      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