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Wyświetlanie 1-15 z 48
Tytuł:
The onset of thermal convection in couple-stress fluid in hydromagnetics saturating a porous medium
Autorzy:
Rana, G. C.
Powiązania:
https://bibliotekanauki.pl/articles/201216.pdf
Data publikacji:
2014
Wydawca:
Polska Akademia Nauk. Czytelnia Czasopism PAN
Tematy:
couple stress fluid
magnetic field
porous medium
thermal convection
Opis:
In this paper, the effect of magnetic field on thermal convection in couple-stress fluid saturating a porous medium is considered. By applying linear stability theory and the normal mode analysis method, a mathematical theorem is derived which states that the viscoelastic thermal convection at marginal state, cannot manifest as stationary convection if the thermal Rayleigh number R, the medium permeability parameter Pι the couple-stress parameter F and the Chandrasekher number Q, satisfy the inequality R ≤4π2/Pl (1 + 2π2F + PlQ/2ε) the result clearly establishes the stabilizing character of couple-stress parameter and magnetic field whereas destabilizing character of medium permeability.
Źródło:
Bulletin of the Polish Academy of Sciences. Technical Sciences; 2014, 62, 2; 357-362
0239-7528
Pojawia się w:
Bulletin of the Polish Academy of Sciences. Technical Sciences
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
On thermal instability of Kuvshiniski fluid with suspended particles saturated in a porous medium in the presence of a magnetic field
Autorzy:
Singh, M.
Powiązania:
https://bibliotekanauki.pl/articles/265476.pdf
Data publikacji:
2017
Wydawca:
Uniwersytet Zielonogórski. Oficyna Wydawnicza
Tematy:
thermal convection
Kuvshiniski fluid
suspended particles
magnetic field
porous medium
Opis:
The thermal instability of a Kuvshiniski viscoelastic fluid is considered to include the effects of a uniform horizontal magnetic field, suspended particles saturated in a porous medium. The analysis is carried out within the framework of the linear stability theory and normal mode technique. For the case of stationary convection, the Kuvshiniski viscoelastic fluid behaves like a Newtonian fluid and the magnetic field has a stabilizing effect, whereas medium permeability and suspended particles are found to have a destabilizing effect on the system, oscillatory modes are introduced in the system, in the absence of these the principle of exchange of stabilities is valid. Graphs in each case have been plotted by giving numerical values to the parameters, depicting the stability characteristics. Sufficient conditions for the avoidance of overstability are also obtained.
Źródło:
International Journal of Applied Mechanics and Engineering; 2017, 22, 4; 981-994
1734-4492
2353-9003
Pojawia się w:
International Journal of Applied Mechanics and Engineering
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
Global stability for thermal convection in a couple-stress fluid with temperature and pressure dependent viscosity
Autorzy:
Choudhary, S. S.
Bharti, P. K.
Powiązania:
https://bibliotekanauki.pl/articles/178230.pdf
Data publikacji:
2013
Wydawca:
Politechnika Wrocławska. Oficyna Wydawnicza Politechniki Wrocławskiej
Tematy:
konwekcja
konwekcja cieplna
stabilność
płyn nieniutonowski
convection
thermal convection
stability
non-Newtonian fluid
Opis:
We show that the global nonlinear stability threshold for convection in a couple-stress fluid with temperature and pressure dependent viscosity is exactly the same as the linear instability boundary. This optimal result is important because it shows that linearized instability theory has captured completely the physics of the onset of convection. It has also been found that the couplestress fluid is more stable than the ordinary viscous fluid and then the effect of couple-stress parameter (F) and variable dependent viscosity (Γ) on the onset of convection is also analyzed.
Źródło:
Studia Geotechnica et Mechanica; 2013, 35, 3; 85-102
0137-6365
2083-831X
Pojawia się w:
Studia Geotechnica et Mechanica
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
Anisotropic turbulent viscosity and large-scale motive force in thermally driven turbulence at low Prandtl number
Autorzy:
Mizerski, K. A.
Powiązania:
https://bibliotekanauki.pl/articles/38695701.pdf
Data publikacji:
2022
Wydawca:
Instytut Podstawowych Problemów Techniki PAN
Tematy:
thermal convection
heat transport
Rayleigh number
Prandtl number
random heat source
Opis:
The fully developed turbulent Boussinesq convection is known to form large-scale rolls, often termed the ‘large-scale circulation’ (LSC). It is an interesting question how such a large-scale flow is created, in particular in systems when the energy input occurs at small scales, when inverse cascade is required in order to transfer energy into the large-scale modes. Here, the small-scale driving is introduced through stochastic, randomly distributed heat source (say radiational). The mean flow equations are derived by means of simplified renormalization group technique, which can be termed a ‘weakly nonlinear renormalization procedure’ based on consideration of only the leading order terms at each step of the recursion procedure, as full renormalization in the studied anisotropic case turns out unattainable. The effective, anisotropic viscosity is obtained and it is shown that the inverse energy cascade occurs via an effective ‘motive force’ which takes the form of transient negative, vertical diffusion.
Źródło:
Archives of Mechanics; 2022, 74, 5; 409-436
0373-2029
Pojawia się w:
Archives of Mechanics
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
Magneto-rotatory compressible couple-stress fluid heated from below in porous medium
Autorzy:
Mehta, C. B.
Powiązania:
https://bibliotekanauki.pl/articles/178540.pdf
Data publikacji:
2016
Wydawca:
Politechnika Wrocławska. Oficyna Wydawnicza Politechniki Wrocławskiej
Tematy:
compressible couple-stress fluid
thermal convection
porous medium
rotation
magnetic field
Opis:
The study is aimed at analysing thermal convection in a compressible couple stress fluid in a porous medium in the presence of rotation and magnetic field. After linearizing the relevant equations, the perturbation equations are analysed in terms of normal modes. A dispersion relation governing the effects of rotation, magnetic field, couple stress parameter and medium permeability have been examined. For a stationary convection, the rotation postpones the onset of convection in a couple stress fluid heated from below in a porous medium in the presence of a magnetic field. Whereas, the magnetic field and couple stress postpones and hastens the onset of convection in the presence of rotation and the medium permeability hastens and postpones the onset of convection with conditions on Taylor number. Further the oscillatory modes are introduced due to the presence of rotation and the magnetic field which were non-existent in their absence, and hence the principle of exchange stands valid. The sufficient conditions for nonexistence of over stability are also obtained.
Źródło:
Studia Geotechnica et Mechanica; 2016, 38, 1; 55-63
0137-6365
2083-831X
Pojawia się w:
Studia Geotechnica et Mechanica
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
Boundary effects on electrothermal convection in a dielectric fluid layer
Autorzy:
Ravisha, M.
Raghunatha, K. R.
Mamatha, A. L.
Shivakumara, I. S.
Powiązania:
https://bibliotekanauki.pl/articles/240648.pdf
Data publikacji:
2019
Wydawca:
Polska Akademia Nauk. Czytelnia Czasopism PAN
Tematy:
boundary effect
dielectric fluid
AC electric field
thermal convection
konwekcja termiczna
płyn dielektryczny
warunki brzegowe
Opis:
The instability characteristics of a dielectric fluid layer heated from below under the influence of a uniform vertical alternating current (AC) electric field is analyzed for different types of electric potential (constant electric potential/ electric current), velocity (rigid/free) and temperature boundary conditions (constant temperature/heat flux or a mixed condition at the upper boundary). The resulting eigenvalue problem is solved numerically using the shooting method for various boundary conditions and the solution is also found in a simple closed form when the perturbation heat flux is zero at the boundaries. The possibility of a more precise control of electrothermal convection (ETC) through various boundary conditions is emphasized. The effect of increasing AC electric Rayleigh number is to hasten while that of Biot number is to delay the onset of ETC. The system is more stable for rigid-rigid boundaries when compared to rigid-free and least stable for free-free boundaries. The change of electric potential boundary condition at the upper boundary from constant electric potential to constant electric current is found to instill more stability on the system.
Źródło:
Archives of Thermodynamics; 2019, 40, 1; 3-19
1231-0956
2083-6023
Pojawia się w:
Archives of Thermodynamics
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
Compressible analysis of Bénard convection of magneto rotatory couple-stress fluid
Autorzy:
Mehta, C. B.
Singh, M.
Powiązania:
https://bibliotekanauki.pl/articles/264669.pdf
Data publikacji:
2018
Wydawca:
Uniwersytet Zielonogórski. Oficyna Wydawnicza
Tematy:
konwekcja termiczna
pole magnetyczne
rotacja
ściśliwość
couple-stress fluid
compressibility
rotation
magnetic field
thermal convection
Opis:
Thermal Instability (Benard’s Convection) in the presence of uniform rotation and uniform magnetic field (separately) is studied. Using the linearized stability theory and normal mode analyses the dispersion relation is obtained in each case. In the case of rotatory Benard’s stationary convection compressibility and rotation postpone the onset of convection whereas the couple-stress have duel character onset of convection depending on rotation parameter. While in the absence of rotation couple-stress always postpones the onset of convection. On the other hand, magnetic field on thermal instability problem on couple-stress fluid for stationary convection couple-stress parameter and magnetic field postpones the onset of convection. The effect of compressibility also postpones the onset of convection in both cases as rotation and magnetic field. Graphs have been plotted by giving numerical values to the parameters to depict the stationary characteristics. Further, the magnetic field and rotation are found to introduce oscillatory modes which were non-existent in their absence and then the principle of exchange of stability is valid. The sufficient conditions for non-existence of overstability are also obtained.
Źródło:
International Journal of Applied Mechanics and Engineering; 2018, 23, 1; 91-105
1734-4492
2353-9003
Pojawia się w:
International Journal of Applied Mechanics and Engineering
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
A dynamically adaptive lattice Boltzmann method for thermal convection problems
Autorzy:
Feldhusen, K.
Deiterding, R.
Wagner, C.
Powiązania:
https://bibliotekanauki.pl/articles/331394.pdf
Data publikacji:
2016
Wydawca:
Uniwersytet Zielonogórski. Oficyna Wydawnicza
Tematy:
lattice Boltzmann method
adaptive mesh refinement
thermal convection
incompressible
metoda siatkowa Boltzmanna
adaptacyjne zagęszczanie siatki
konwekcja termiczna
Opis:
Utilizing the Boussinesq approximation, a double-population incompressible thermal lattice Boltzmann method (LBM) for forced and natural convection in two and three space dimensions is developed and validated. A block-structured dynamic adaptive mesh refinement (AMR) procedure tailored for the LBM is applied to enable computationally efficient simulations of moderate to high Rayleigh number flows which are characterized by a large scale disparity in boundary layers and free stream flow. As test cases, the analytically accessible problem of a two-dimensional (2D) forced convection flow through two porous plates and the non-Cartesian configuration of a heated rotating cylinder are considered. The objective of the latter is to advance the boundary conditions for an accurate treatment of curved boundaries and to demonstrate the effect on the solution. The effectiveness of the overall approach is demonstrated for the natural convection benchmark of a 2D cavity with differentially heated walls at Rayleigh numbers from 103 up to 108. To demonstrate the benefit of the employed AMR procedure for three-dimensional (3D) problems, results from the natural convection in a cubic cavity at Rayleigh numbers from 103 up to 105 are compared with benchmark results.
Źródło:
International Journal of Applied Mathematics and Computer Science; 2016, 26, 4; 735-747
1641-876X
2083-8492
Pojawia się w:
International Journal of Applied Mathematics and Computer Science
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
Triple- diffusive convection in a micropolar ferrofluid in the presence of rotation
Autorzy:
Chand, S.
Powiązania:
https://bibliotekanauki.pl/articles/265647.pdf
Data publikacji:
2013
Wydawca:
Uniwersytet Zielonogórski. Oficyna Wydawnicza
Tematy:
konwekcja
konwekcja cieplna
substancja rozpuszczalna
pole magnetyczne
namagnesowanie
triple- diffusive convection
micropolar ferrofluid
thermal convection
solute gradient
vertical magnetic field
rotation
magnetization
Opis:
This paper deals with the theoretical investigation of the triple-diffusive convection in a micropolar ferrofluid layer heated and soluted below subjected to a transverse uniform magnetic field in the presence of uniform vertical rotation. For a flat fluid layer contained between two free boundaries, an exact solution is obtained. A linear stability analysis theory and normal mode analysis method have been employed to study the onset convection. The influence of various parameters like rotation, solute gradients, and micropolar parameters (i.e., the coupling parameter, spin diffusion parameter and micropolar heat conduction parameter) on the onset of stationary convection has been analyzed. The critical magnetic thermal Rayleigh number for the onset of instability is also determined numerically for sufficiently large value of the buoyancy magnetization parameter M1 (ratio of the magnetic to gravitational forces). The principle of exchange of stabilities is found to hold true for the micropolar fluid heated from below in the absence of micropolar viscous effect, microinertia, solute gradient and rotation. The oscillatory modes are introduced due to the presence of the micropolar viscous effect, microinertia , solute gradient and rotation, which were non-existent in their absence. In this paper, an attempt is also made to obtain the sufficient conditions for the non-existence of overstability.
Źródło:
International Journal of Applied Mechanics and Engineering; 2013, 18, 2; 307-327
1734-4492
2353-9003
Pojawia się w:
International Journal of Applied Mechanics and Engineering
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
Analysis of thermal stratified storage tank
Autorzy:
Smusz, R.
Kielan, P.
Mazur, D.
Powiązania:
https://bibliotekanauki.pl/articles/140948.pdf
Data publikacji:
2017
Wydawca:
Polska Akademia Nauk. Czytelnia Czasopism PAN
Tematy:
temperature stratification
thermal energy
heat recovery
convection
Opis:
The basic aim of the task is to compile a temperature stratification system in an accumulation tank. The range of the thesis concerns the shape and dimensions of a stratification system for an accumulation tank. Thermal stratification is a process that comprises the maintaining of temperature stratification at different levels of an accumulation tank which reduce to a minimum the process of temperature equalization. It results from the fact that the thermal stratification in a tank significantly increases the installation efficiency and improves the process of energy storing. It is connected with a thermodynamic element quality, that is the higher the temperature, the higher the energy, and, thus, the thermosdynamic element quality. In this phenomenon, thanks to the same amount of accumulated thermal energy and average temperature, as in a fully mixed tank, the user has a higher temperature in the upper part of the tank at his disposal. It has significant importance in the case when there is a low-temperature heating medium that transfers heat to the accumulation tank. Such a situation occurs when heat is absorbed from synthetic freons used in cooling and air-conditioning systems.
Źródło:
Archives of Electrical Engineering; 2017, 66, 3; 631-642
1427-4221
2300-2506
Pojawia się w:
Archives of Electrical Engineering
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
Zastosowanie CFD do oceny przepływu powietrza w strumieniach konwekcyjnych kształtujących się nad człowiekiem
CFD simulationm of thermal plumes formed above human subject
Autorzy:
Bogdan, A.
Powiązania:
https://bibliotekanauki.pl/articles/362848.pdf
Data publikacji:
2010
Wydawca:
Instytut Fizyki Budowli Katarzyna i Piotr Klemm
Tematy:
strumienie konwekcyjne
manekin termiczny
CFD
convection streams
thermal manikin
Opis:
Poznanie zachowania strumieni konwekcyjnych kształtujących się nad człowiekiem jest istotne ze względu na wymagania wentylacji pomieszczeń, jakości powietrza wewnętrznego oraz komfortu cieplnego użytkowników. W referacie przedstawiono wyniki badań przeprowadzonych przy wykorzystaniu metod CFD, w celu analizy możliwości i ograniczeń w symulacjach strumieni konwekcyjnych rozwijających się nad człowiekiem. W symulacjach zastosowano numerycznego manekina termicznego, będącego w pozycji siedzącej, o geometrii zgodnej z geometrią rzeczywistego ciała człowieka. Wyniki symulacji CFD porównano z wynikami badań prędkości powietrza w strumieniu konwekcyjnym formującym się nad manekinem termicznym (rzeczywistym) i człowiekiem.
The behavior of the buoyant plume of air shed by a human being in an indoor environment is important to room ventilation requirements, indoor air quality and the thermal comfort of building occupants. In the tests described in this paper computational fluid dynamics (CFD) was used to analyze the possibilities and limitations of simulating thermal plumes developing above the human. In simulations a sealed computalional thermal manikin with geometry of a real human body was used. Results from CFD were compared with the results of real measurements of air velocities in thermal plume forming over the thermal manikin and the human.
Źródło:
Fizyka Budowli w Teorii i Praktyce; 2010, T. 5, nr 1, 1; 11-14
1734-4891
Pojawia się w:
Fizyka Budowli w Teorii i Praktyce
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
Optymalizacja termiczna położenia elementów elektronicznych w interfejsie wizyjno-akustycznym systemu wspomagania niewidomego w samodzielnym poruszaniu się
: Thermal optimization of electronic device placement in a video-and-sound interface of the system assisting the blind in independent mobility
Autorzy:
Ostrowski, B.
Felczak, M.
Tomalczyk, K.
Powiązania:
https://bibliotekanauki.pl/articles/155489.pdf
Data publikacji:
2013
Wydawca:
Stowarzyszenie Inżynierów i Techników Mechaników Polskich
Tematy:
optymalizacja termiczna
przewodzenie ciepła
konwekcja
niewidomi
thermal optimization
thermal conductivity
convection
visually impaired persons
Opis:
W artykule omówiono zagadnienie optymalizacji rozmieszczenia komponentów układu elektronicznego celem minimalizacji temperatury podczas jego pracy. Optymalizacja została przeprowadzona na przykładzie sprzętowego interfejsu wizyjno-akustycznego systemu wspomagania niewidomego w samodzielnym poruszaniu się. Rozmieszczenie komponentów na zadanym obszarze płytki PCB zostało zoptymalizowane przy użyciu opracowanego przez autorów algorytmu ewolucyjnego składającego się z dwóch etapów obliczeń [1]. W wyniku zastosowania algorytmu uzyskano rozmieszczenie komponentów, dla którego tak maksymalna, jak i średnia temperatura płytki PCB nie powodują dyskomfortu dla użytkownika. Pomiary termowizyjne potwierdzają poprawność uzyskanych wyników.
The paper deals with the problem of optimal electronic component placement on a PCB in order to obtain the lowest possible, given the design limitations, maximum and average electronic circuit temperatures. The optimization is applied to an exemplary electronic device, which is a video-and-sound interface of the system assisting the blind in independent mobility. The majority of optimization algorithms is based on large-scale sparse matrix calculations. The authors propose an alternative approach, using an original idea of an evolution algorithm [1]. The algorithm is implemented in Delphi 7 programming language and utilizes the ANSYS 11 modeling environment for temperature calculations. The device to be optimized contains a stereovision camera system, a set of inertial sensors, a microcontroller, a sound adapter and a USB hub for a mobile computer data exchange (Fig. 1). The prototype has a form of glasses with integrated inter-aural headphones (Fig. 2). The device dissipates 3.1 W of heat during its operation, with the USB hub and LDO voltage regulator identified as the hottest spots. The cameras also emit considerable amounts of heat, they are however excluded from the placement optimization, due to their exact position requirement. The PCB was modeled with a 2D 1mm grid applied to a simplified representation of the PCB actual shape (Fig. 3). The algorithm required 194 iterations to return an optimal placement (Fig. 4) with average PCB temperature approx. 22°C, the hottest spot not exceeding 35°C. Such a temperature level allows the video-and-sound interface to be operated with no compromise on user’s safety and comfort. The device was re-designed, built and tested according to the obtained optimal component placement. The thermal imaging measurements (Fig. 5) are in good accordance with the temperature calculation results from the algorithm.
Źródło:
Pomiary Automatyka Kontrola; 2013, R. 59, nr 9, 9; 882-884
0032-4140
Pojawia się w:
Pomiary Automatyka Kontrola
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
Unsteady hydromagnetic mixed convection of a radiating and reacting nanofluid in a microchannel with variable properties
Autorzy:
Kefene, Mesfin Zewde
Makinde, Oluwole Daniel
Enyadene, Lemi Guta
Powiązania:
https://bibliotekanauki.pl/articles/38890072.pdf
Data publikacji:
2023
Wydawca:
Instytut Podstawowych Problemów Techniki PAN
Tematy:
nanofluid
mixed convection
permeable microchannel
Buongiorno’s model
thermal radiation
Opis:
Unsteady MHD mixed convection of nanofluid heat transfer in a permeable microchannel with temperature-dependent fluid properties is studied under the influence of a first-order chemical reaction and thermal radiation. The viscosity and thermal conductivity are assumed to be related to temperature exponentially. Using suitable dimensionless variables and parameters, the governing partial differential equations (PDEs) are transformed to their corresponding dimensionless forms solved numerically by a semi-discretization finite difference scheme along with the Runge-Kutta-Fehlberg integration technique. The effects of model parameters on the profiles of velocity, temperature, concentration, skin friction, the Nusselt number, and the Sherwood number are discussed qualitatively with the aid of graph.
Źródło:
Engineering Transactions; 2023, 71, 1; 53-79
0867-888X
Pojawia się w:
Engineering Transactions
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
Finite Different Analysis of Free Convection Flow and Heat Transfer of Casson Nanofluid over a Vertical Plate under the Influence of Thermal Radiation
Autorzy:
Sobamowo, M. G.
Okolie, A. C.
Powiązania:
https://bibliotekanauki.pl/articles/1193438.pdf
Data publikacji:
2021
Wydawca:
Przedsiębiorstwo Wydawnictw Naukowych Darwin / Scientific Publishing House DARWIN
Tematy:
Casson fluid
Free convection
Nanoparticle
Numerical solutions
Prandtl number
Thermal radiation
Opis:
In this paper, a numerical study on free convection flow and heat transfer of Casson nanofluids over a vertical plate under the influence of thermal radiation is carried out. The governing systems of coupled nonlinear partial differential equations of the flow and heat transfer processes are converted to a system of coupled nonlinear ordinary differential equations through suitable similarity variables. The obtained ordinary differential equations are solved using finite difference method. The results of the numerical solutions are compared with the results of past works as presented in literature and good agreement was established. Also, the effects of thermal radiation; Prandtl number, nanoparticles volume-fraction, shape and type on the flow and heat transfer behaviour of various nanofluids over the flat plate are investigated. The results show that the magnitude of velocity near the plate for the Casson nanofluid parameter decreases for increasing value of the Casson parameter, while temperature increases for increase in Casson fluid parameter. Also, the thermal radiation and volume-fraction of the nanoparticles in the base fluid increase, the velocity, temperature, viscous and thermal boundary layers of the nanofluid increase. However, the velocity of the nanofluid decreases as the Prandtl number increases while the temperature of the nanofluid increases as the Prandtl number increases. The velocity of the nanofluid decreases as the volume-fraction or concentration of the nanoparticle in the base fluid increases. The study can benefit the design engineers enhancing their understanding of the phenomenon for various industrial and engineering applications.
Źródło:
World Scientific News; 2021, 157; 38-66
2392-2192
Pojawia się w:
World Scientific News
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
Thermodynamic analysis of radiating nanofluids mixed convection within concentric pipes filled with a porous medium
Autorzy:
Makinde, Oluwole Daniel
Mabood, Fazle
Khan, Waqar Ahmed
Makinde, Anuoluwa Esther
Powiązania:
https://bibliotekanauki.pl/articles/38910057.pdf
Data publikacji:
2023
Wydawca:
Instytut Podstawowych Problemów Techniki PAN
Tematy:
nanofluid
concentric pipes
mixed convection
thermal radiation
porous medium
entropy analysis
Opis:
In this study, the entropy generation resulting from heat and mass transfer of waterbased nanofluid through an annulus within two concentric vertical pipes filled with a porous medium is investigated. This study considers the effects of thermal radiation, viscous dissipation, thermal buoyancy, and axial pressure gradient in addition to heat and mass transfer. Brownian motion and thermophoresis have been introduced through the Buongiorno model. The similarity solution was used to solve nonlinear ordinary differential equations. The RungeKutta-Fehlberg method is used to solve these equations with the related boundary conditions. The effects of pertinent parameters such as pressure gradient, thermal radiation, viscosity parameter, thermophoretic parameter, Brownian motion parameter, and Eckert number are investigated numerically. This study found that the Bejan number increases as the viscosity parameter increases and decreases as the other active parameters increase. As the radiation parameter, thermophoretic parameter, Brownian parameter, and Eckert number increase, the Nusselt number decreases. The total entropy generation rate is found to increase with the fluid viscosity rate, Grashof number, thermal Biot number, and variable pressure gradient. However, the Bejan number is found to decrease with these parameters, as well as the Prandtl number.
Źródło:
Engineering Transactions; 2023, 71, 3; 419-438
0867-888X
Pojawia się w:
Engineering Transactions
Dostawca treści:
Biblioteka Nauki
Artykuł
Wyświetlanie 1-15 z 48

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