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Tytuł:
Cross-waves and pulsating flows in the side-channel spillway - an experimental approach
Autorzy:
Azmeri, Azmeri
Ummah, Chairatun
Jemi, Faris Zahran
Faudli, Imam
Nasaiy, Qurratul 'Aini Benti
Powiązania:
https://bibliotekanauki.pl/articles/2203528.pdf
Data publikacji:
2023
Wydawca:
Instytut Technologiczno-Przyrodniczy
Tematy:
cross-waves
hydrodynamic force
physical model
pulsating flow
side-channel spillway
Opis:
Potentially hazardous side-channels of complex geometry need to be investigated using detailed hydraulic physical models. This study aims to analyse the cross-waves pattern and pulsating flow using a side-channel spillway physical model. This study compares the cross-waves pattern were measured using an experimental installation set to generate cross-waves on the surface (original series) with another structure that did not produce cross-waves (modified series). The results showed that the geometry of the left wall caused instability in flow patterns and secondary flows. The starting point of Q2 discharge was detected by minor turbulence on the water surface near the left wall at a water depth of 3.3 m at the starting point of the wall, but with no overtopping. Cross-waves formed downstream at the right wall crosswise, lower than at the left wall. The height of the cross-wave increased substantially from Q100 to Q1000 discharges leading to overtoppings near the left wall at a water depths of 4.2 and 5.0 m at the starting point of the wall, and near the right wall at a water depths of 3.8 and 4.0 m at the upstream point of the wall. The modifications provided optimal hydraulic conditions, i.e. elimination of cross-waves and non-uniform flows. The Vedernikov and Montouri numbers showed that both original and modified series did not enter the area where the pulsating flow occurred. This indicated that both series were free from the pulsating flow.
Źródło:
Journal of Water and Land Development; 2023, 56; 51--57
1429-7426
2083-4535
Pojawia się w:
Journal of Water and Land Development
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
Simulation of laminar flow passing through a T-splitter plate and bridge pier.
Autorzy:
Qasim, Rafi Mohammed
Jabbar, Tahseen Ali
Faisal, Safaa Hameed
Powiązania:
https://bibliotekanauki.pl/articles/36063658.pdf
Data publikacji:
2023
Wydawca:
Szkoła Główna Gospodarstwa Wiejskiego w Warszawie. Wydawnictwo Szkoły Głównej Gospodarstwa Wiejskiego w Warszawie
Tematy:
hydrodynamic
laminar flow
open channel
pier
splitter plate
Opis:
The present analysis focuses on the investigation of the two-dimensional flow passing a bridge pier nearby a splitter plate in different regimes of a laminar flow. The splitter plate is T-shaped and two different cases have been studied based on the form of the splitter plate relative to the bridge pier. The analysis is implemented for steady and incompressible water flow in an open channel. The current study deals with velocity vectors, drag coefficients, lift coefficients, and skin friction. The analysis of the velocity vector gave a good indicator about the separation process and dissipation, which occurs at the splitter plate before the occurrence of these processes at the front face of the pier, especially the flow separation process. Moreover, the velocity vector gave a good image about the flow direction at two regions, the first region is located between the rear portion of the splitter plate and the frontal face of the pier, while the second region is the wake region, which is located at the downstream of the pier. Negative drag coefficient, lift coefficient, and skin friction coefficient values are obtained from the analysis. This happens due to the existence of the splitter plate that leads to the reduction of these values.
Źródło:
Scientific Review Engineering and Environmental Sciences; 2023, 32, 2; 135-154
1732-9353
Pojawia się w:
Scientific Review Engineering and Environmental Sciences
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
Static instability of an inverted plate in channel flow: state-space representation and solution approximation
Autorzy:
Li, P.
Zhang, D.
Cui, J.
Yin, H.
Yang, Y.
Powiązania:
https://bibliotekanauki.pl/articles/38697113.pdf
Data publikacji:
2023
Wydawca:
Instytut Podstawowych Problemów Techniki PAN
Tematy:
inverted cantilevered plate
static aeroelastic instability
channel flow
state-space representation
Glauert’s series
the least squares method
Opis:
Plate-like structures in channel flow are commonly found in engineering. This paper reports a theoretical study on the static aeroelastic instability of an inverted cantilevered plate in an inviscid channel flow through the state space. This study begins with the kernel function of the flow potential determined in the Fourier domain with the help of the mirror image method. Then, the instability equation is derived from the operator theory and transformed in the state space. Finally, with Glauert’s expansion, model functions, and error functions, the instability problem of such a plate has been modeled as a mathematical function approximation problem and solved by the least squares method. The derived instability equation is considered at the continuum level of description, and no approximation appears at the first equation level. The convergence and reliability of the proposed modeling and its solutions approximation are entirely tested, and it can successfully predict the instability boundary, behavior, and the channel effect. Numerical results show that the decreased channel height and asymmetric plate placement in the channel significantly decrease the critical flow velocity. The plate instability modes are close to the plate’s first natural ones and not sensitive to the channel parameters. This conclusion allows further theoretical exploration of a semi-analytical approximation of the instability boundary from the obtained instability equation. The current modeling strategy in a continuum sense may provide a new idea and essential reference for other instability problems.
Źródło:
Archives of Mechanics; 2023, 75, 6; 695-727
0373-2029
Pojawia się w:
Archives of Mechanics
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
Practical aspects of the use of the sluice gate discharge equations to estimate the volumetric flow rate in the irrigation channels
Autorzy:
Kubrak, Elżbieta
Kubrak, Janusz
Powiązania:
https://bibliotekanauki.pl/articles/2174345.pdf
Data publikacji:
2022
Wydawca:
Instytut Technologiczno-Przyrodniczy
Tematy:
discharge coefficient
discharge calculation error
irrigation channel
laboratory model investigations
submerged sluice gate flow
volumetric flow rate
Opis:
The article presents the experimental results of the calibration of the typical check structure with sluice gates installed in a trapezoidal irrigation channel. Hydraulic experiments on sluice gate discharge capacity were performed on a model made in a 1:2 scale. It has been explained how the method of measuring the downstream water depth below the sluice gate in the check structures installed in a trapezoidal irrigation channels affects the measured depth values. On the basis of hydraulic measurements, regression relationships were developed for the discharge coefficients for submerged outflow through the sluice gate in two types of sluice gates installed in irrigation channels. The formulas allow to calculate the volumetric flow rate below the submerged sluice gate after determining the water depth upstream and below the sluice gate and the gate opening height. The differences in volumetric flow rates calculated from regression relationships and measured values do not exceed 10%, which confirms their practical suitability for calculating the discharge through a sluice gate mounted in a trapezoidal channel. The values of the discharge coefficients determined in the channels with rectangular cross-sections are not useful for the discharge coefficients of sluice gates check structures installed in trapezoidal channels. Nomograms and relationships for discharge coefficients of the analysed sluice gate were developed.
Źródło:
Journal of Water and Land Development; 2022, 55; 129--137
1429-7426
2083-4535
Pojawia się w:
Journal of Water and Land Development
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
Second law analysis of mhd forced convective nanoliquid flow through a two-dimensional channel
Autorzy:
Miri, Rached
Abbassi, Mohamed A.
Ferhi, Mokhtar
Djebali, Ridha
Powiązania:
https://bibliotekanauki.pl/articles/2204682.pdf
Data publikacji:
2022
Wydawca:
Politechnika Białostocka. Oficyna Wydawnicza Politechniki Białostockiej
Tematy:
MHD
LBM
channel flow
nanoliquids
entropy generation
Brownian motion
Opis:
The present study deals with fluid flow, heat transfer and entropy generation in a two-dimensional channel filled with Cu–water nanoliquid and containing a hot block. The nanoliquid flow is driven along the channel by a constant velocity and a cold temperature at the inlet, and the partially heated horizontal walls. The aim of this work is to study the influence of the most important parameters such as nanoparticle volume fraction (0%≤ϕ≤4%), nanoparticle diameter (5 nm≤dp≤55 nm), Reynolds number (50≤Re≤200), Hartmann number (0≤Ha≤90), magnetic field inclination angle (0≤γ≤π) and Brownian motion on the hydrodynamic and thermal characteristics and entropy generation. We used the lattice Boltzmann method (LBM: SRT-BGK model) to solve the continuity, momentum and energy equations. The obtained results show that the maximum value of the average Nusselt number is found for case (3) when the hot block is placed between the two hot walls. The minimum value is calculated for case (2) when the hot block is placed between the two insulated walls. The increase in Reynolds and Hartmann numbers enhances the heat transfer and the total entropy generation. In addition, the nanoparticle diameter increase reduces the heat transfer and the irreversibility, the impact of the magnetic field inclination angle on the heat transfer and the total entropy generation is investigated, and the Brownian motion enhances the heat transfer and the total entropy generation.
Źródło:
Acta Mechanica et Automatica; 2022, 16, 4; 417--431
1898-4088
2300-5319
Pojawia się w:
Acta Mechanica et Automatica
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
Modeling the hydrodynamic interactions between the river morphology and navigation channel operations
Autorzy:
Badawy, Neveen Abdel-Mageed
El-Hazek, Alaa N.
Elsersawy, Hossam Mohamed
Mohammed, Ebtesam Rezk
Powiązania:
https://bibliotekanauki.pl/articles/2048502.pdf
Data publikacji:
2021
Wydawca:
Instytut Technologiczno-Przyrodniczy
Tematy:
adaptive hydraulics (ADH) model
draw down
navigation channel
the Nile River
restricted waterway
return flow
shear stress
Opis:
The Nile River is the main route for inland navigation in Egypt. The vessels navigating through inland waterways generate complex physical forces that need to be studied extensively. Quantifying the effects of vessels sailing along a waterway is a complex problem because the river flow is unsteady and the river bathymetry is irregular. This paper aims to investigate the hydrodynamic effects resulting from the movement of vessels such as return currents around the vessel, the draw down of the water surface, under keel clearance, and the shear stress induced by vessels operating in the Nile River. Modeling such effects has been performed by applied the two-dimensional ADH (adaptive hydraulics) model to a river reach for different navigation channel operation scenarios. The obtained results show that the draw down heights, the water fluctuation, and the shear stress magnitude are larger when the river cross sectionals are narrow and the shallow water depths. These river sections are considered more disposed to bed erosion and it is morphologically unsafe. The section having the narrowest width and the lowest depth was associated with the largest drawdown percentages of 98.3% and 87.3% in one-way and two-way scenarios. While the section having the widest width and the largest depth was associated with the least drawdown percentages of 48.5% and 51.9% in one-way and two-way scenarios. The section having the narrowest width and the lowest depth was associated with the largest fluctuations of 22.0 cm and 41.9 cm in one-way and two-way scenarios. While the section having the widest width and the largest depth was associated with the least fluctuations of 0.6 cm and 1.8 cm in one-way and two-way scenarios. The section having the narrowest width and the lowest depth was the worst section for under keel clearance of 5.0 cm and 33.3 cm in one-way and two-way scenarios. While the section having the widest width and the largest depth was the best section, where its clearance values were 183.2 cm and 155.0 cm in one-way and two-way scenarios. It is concluded that a numerical model is a valuable tool for predicting and quantifying the hydrodynamic effects of vessels moving through a two-dimensional flow field and can be used to evaluate different scenarios that are difficult to measure in the field or a physical model. Also, it provides visualization products that help us understand the complicated forces produced by vessels moving in a navigation channel.
Źródło:
Journal of Water and Land Development; 2021, 51; 1-10
1429-7426
2083-4535
Pojawia się w:
Journal of Water and Land Development
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
Numerical study on two dimensional distribution of streamwise velocity in open channel turbulent flows with secondary current effect
Autorzy:
Mohan, S.
Kundu, S.
Ghoshal, K.
Kumar, J.
Powiązania:
https://bibliotekanauki.pl/articles/38616700.pdf
Data publikacji:
2021
Wydawca:
Instytut Podstawowych Problemów Techniki PAN
Tematy:
velocity distribution
open channel flow
turbulent flow
RANS equations
secondary current
finite difference method
Opis:
For studying mechanism of sediment transport in river flows, open channel flow is a prototype. Flow has always three components of velocity for all types of channel geometry and for a time independent uniform flow along streamwise or main flow direction, all the components of velocity are functions of lateral and vertical coordinates. The present study investigates the two dimensional distribution of streamwise (or longitudinal) velocity starting from the Reynolds averaged Navier–Stokes equation for a turbulent open channel flow which is steady and uniform along the main flow direction. Secondary flows both along the vertically upward direction and along the lateral direction are considered which are also taken as functions of lateral and vertical coordinates. Inclusion of the secondary current brings the effect of dip phenomenon in the model. The resulting second order partial differential equation is solved numerically. The model is validated for all the cross-sectional, transverse and centreline velocity distribution by comparing with existing relevant set of experimental data and also with an existing model. Comparison results show good agreement with data as well as with the previous model proving the efficiency of the model. It is found that the transverse velocity distribution depends on the formation of circular vortex in the cross-sectional plane and becomes periodic as the number of circular vortex increases for increasing aspect ratios.
Źródło:
Archives of Mechanics; 2021, 73, 2; 175-200
0373-2029
Pojawia się w:
Archives of Mechanics
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
Validation of a flow channel to investigate velocity profiles of friction-reducing ship coatings
Autorzy:
Weisheit, J.
Schneider, V. E.
Serr, J. M.
Hagemeister, N.
Oeffner, J.
Powiązania:
https://bibliotekanauki.pl/articles/1841545.pdf
Data publikacji:
2021
Wydawca:
Uniwersytet Morski w Gdyni. Wydział Nawigacyjny
Tematy:
ship coatings
flow Channel
vessel velocity
laser Doppler velocimeter
computational fluid dynamics
AIRCOAT project
reynolds averaged navier stokes
measurement volume
Opis:
Reducing friction with specialised hull coatings or air lubrication technologies has a potential reducing energy consumption and emissions in shipping. The EU project AIRCOAT combines both by developing a passive air lubrication technology inspired by nature that is implemented on a self-adhesive foil system. Besides validating the friction reduction it is of high interest to understand the underlying mechanism that causes the reduction. Therefore, a flow channel was designed, that creates a stationary turbulent flow within a square duct allowing for non-invasive measurements by laser doppler velocimetry. The high spatial resolution of the laser device makes recording velocity profiles within the boundary layer down to the viscous sublayer possible. Determination of the wall shear stress τ enables direct comparison of different friction reduction experiments. In this paper we validate the methodology by determining the velocity profile of the flat channel wall (without coatings). We further use the results to validate a CFD model in created in OpenFOAM. We find that velocities along the longitudinal axis are generally in good agreement between numerical and experimental investigations.
Źródło:
TransNav : International Journal on Marine Navigation and Safety of Sea Transportation; 2021, 15, 1; 225-231
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 new approach for study the electrohydrodynamic oscillatory flow through a porous medium in a heating compliant channel
Autorzy:
Haroun, M. H.
Powiązania:
https://bibliotekanauki.pl/articles/1839817.pdf
Data publikacji:
2020
Wydawca:
Uniwersytet Zielonogórski. Oficyna Wydawnicza
Tematy:
przepływ oscylacyjny
elektrohydrodynamika
wymiana ciepła
oscillatory flow
electrohydrodynamics
porous medium
heat transfer
compliant channel
Opis:
The governing equations of an electrohydrodynamic oscillatory flow were simplified, using appropriate nondimensional quantities and the conversion relationships between fixed and moving frame coordinates. The obtained system of equations is solved analytically by using the regular perturbation method with a small wave number. In this study, modified non-dimensional quantities were used that made fluid pressure in the resulting equations dependent on both axial and vertical coordinates. The current study is more realistic and general than the previous studies in which the fluid pressure is considered functional only in the axial coordinate. A new approach enabled the author to find an analytical form of fluid pressure while previous studies have not been able to find it but have found only the pressure gradient. Analytical expressions for the stream function, electrical potential function and temperature distribution are obtained. The results show that the electrical potential function decreases by the increase of the Prandtl number, secondary wave amplitude ratio and width of the channel.
Źródło:
International Journal of Applied Mechanics and Engineering; 2020, 25, 3; 30-44
1734-4492
2353-9003
Pojawia się w:
International Journal of Applied Mechanics and Engineering
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
Application of variation of the parameters method for micropolar flow in a porous channel
Autorzy:
Güngör, Osman
Arslantürk, Cihat
Powiązania:
https://bibliotekanauki.pl/articles/1839802.pdf
Data publikacji:
2020
Wydawca:
Politechnika Częstochowska. Wydawnictwo Politechniki Częstochowskiej
Tematy:
micropolar flow
porous channel
variation of parameters method
przepływ mikropolarny
metoda zmiany parametrów
kanał porowaty
Opis:
This work devoted to study the injective micropolar flow in a porous channel. The flow is driven by suction or injection on the channel walls, and the micropolar model is used to characterize the working fluid. The governing nonlinear partial differential equations are reduced to the nonlinear ordinary coupled differential equations by using Berman’s similarity transformation. These equations are solved for large mass transfer via variation of parameters method (VPM) which has been used effectively in the solution of nonlinear equations recently. This method has not previously been applied to a problem of micropolar flow. The results of the variation of parameters method are found to be in excellent agreement with the results of the Matlab bvp4c solver (NUM). With this validity, the effects of the some important parameters on the velocity and rotation profile of micropolar flow are discussed in detail. It can be seen that increases in the values N1 and N3 have different results in comparison with N2 increasing.
Źródło:
Journal of Applied Mathematics and Computational Mechanics; 2020, 19, 1; 17-29
2299-9965
Pojawia się w:
Journal of Applied Mathematics and Computational Mechanics
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
Application of variation of the parameters method for micropolar flow in a porous channel
Autorzy:
Güngör, Osman
Arslantürk, Cihat
Powiązania:
https://bibliotekanauki.pl/articles/122970.pdf
Data publikacji:
2020
Wydawca:
Politechnika Częstochowska. Wydawnictwo Politechniki Częstochowskiej
Tematy:
micropolar flow
porous channel
variation of parameters method
przepływ mikropolarny
metoda zmiany parametrów
kanał porowaty
Opis:
This work devoted to study the injective micropolar flow in a porous channel. The flow is driven by suction or injection on the channel walls, and the micropolar model is used to characterize the working fluid. The governing nonlinear partial differential equations are reduced to the nonlinear ordinary coupled differential equations by using Berman’s similarity transformation. These equations are solved for large mass transfer via variation of parameters method (VPM) which has been used effectively in the solution of nonlinear equations recently. This method has not previously been applied to a problem of micropolar flow. The results of the variation of parameters method are found to be in excellent agreement with the results of the Matlab bvp4c solver (NUM). With this validity, the effects of the some important parameters on the velocity and rotation profile of micropolar flow are discussed in detail. It can be seen that increases in the values N1 and N3 have different results in comparison with N2 increasing.
Źródło:
Journal of Applied Mathematics and Computational Mechanics; 2020, 19, 1; 17-29
2299-9965
Pojawia się w:
Journal of Applied Mathematics and Computational Mechanics
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
Cash flow sensitivity of investment: Evidence from the Polish listed companies
Autorzy:
Nehrebecki, Marian
Powiązania:
https://bibliotekanauki.pl/articles/1356332.pdf
Data publikacji:
2020-10-28
Wydawca:
Uniwersytet Warszawski. Wydział Nauk Ekonomicznych
Tematy:
investment
cash flow
ICFS
balance sheet channel
financial accelerator
Opis:
The paper focuses on assessment of the sensitivity of investment on cash flow (ICFS) made by listed companies in Poland. Achieving this goal will also involve analysing and drawing conclusions about the balance-sheet channel of monetary transmission. An empirical part uses data from financial statements for Poland derived from Emerging Markets Information Services (EMIS), related to companies listed on the Warsaw Stock Exchange and NewConnect. Estimations were made using the Ordinary Least Squares method with robust standard errors, and results made it clear that cash flow has a positive significant impact, indicating that most companies operate on the imperfect and incomplete market, and with constrained or costly access to external financing. Further, it is found that the impact is significantly strong in the slowdown, as financial constraints are more binding. These results seem to confirm that the balance-sheet channel of monetary transmission is operative in Poland.
Źródło:
Central European Economic Journal; 2020, 7, 54; 157 - 171
2543-6821
Pojawia się w:
Central European Economic Journal
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
Numerical simulation of channel flow over a skewed equilateral cavity
Autorzy:
Kamel, Abanoub G.
Haraz, Eman H.
Hanna, Sarwat N.
Powiązania:
https://bibliotekanauki.pl/articles/1839759.pdf
Data publikacji:
2020
Wydawca:
Politechnika Częstochowska. Wydawnictwo Politechniki Częstochowskiej
Tematy:
finite difference method
incompressible flow
channel flow
lid-driven
shear-driven
skewed cavity
Navier-Stokes equations
równanie Naviera-Stokesa
przepływ nieściśliwy
metoda różnic skończonych
przepływ kanałowy
Opis:
In this paper, an incompressible, two-dimensional (2D), time-dependent, Newtonian, laminar, and internal channel fluid flow over a skewed equilateral cavity is simulated using the finite difference method (FDM) and alternating direction implicit (ADI) technique. Navier-Stokes equations are solved numerically in stream function-vorticity formulation. The goal of tackling this problem depends on its academic significance by studying the difference between lid-driven and shear-driven cavity flows in terms of the formation of Moffatt eddies at the sharp corner, also to obtain the length and intensity ratios of these counter-rotating vortices. The value of velocity components along the centerlines of the skewed cavity was revealed at low and intermediate Reynolds numbers (Re), typically (Re = 200 and 2000) at two different skew angles of mainly 30° and 45°. Likewise, the blocked-off regions’ method is used to deal with the geometry of the skewed cavity especially the sharp corners. Furthermore, as Re increases, the main vortex approaches the skewed cavity center and the counter-rotating vortices get bigger in size and intensity, and their number increases.
Źródło:
Journal of Applied Mathematics and Computational Mechanics; 2020, 19, 3; 29-43
2299-9965
Pojawia się w:
Journal of Applied Mathematics and Computational Mechanics
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
Rheodynamics non-viscous medium in long (cylindrical) pipes: using the Ostwald-De Ville model
Autorzy:
Brovatets, Oleksandr
Chоvniuk, Yuiry
Moskvitina, Anna
Powiązania:
https://bibliotekanauki.pl/articles/1833884.pdf
Data publikacji:
2020
Wydawca:
Polska Akademia Nauk. Oddział w Lublinie PAN
Tematy:
rheodynamics
nonlinear viscous medium
long channels
round channel sections
rectangular channel sections
Ostwald-de Waele model
heat transfer
non-isothermal flow
heat exchangers
polyethylene glycol
ethylene glycol
Opis:
While heating the soil in greenhouses, ground heat exchangers are used, as well as when accumulating heat in soil massifs for further use of heat by heat pumps, or when accumulating heat from solar collectors in heat accumulators. In such cases, a coolant moves in the heat exchangers, which will not freeze or boil, most often these are solutions polyethylene/ethylene glycol, which belong to nonlinear viscous fluids. In this work, the nonisothermal motion of a nonlinear-viscous fluid (within the framework of the Ostwald - de Ville model) in a flat channel with a given heat flow on the wall is investigated. A characteristic feature of the flow of such media is their high thermal sensitivity due to phase and structural transformations. Therefore, with a change in temperature, there is a sharp change in rheological properties. For a number of materials, for example, for polyethylene glycol (ethylene glycol) mixtures, for glycerol solutions, these changes can occur in a fairly narrow temperature range. The flow in a channel is considered, the length of which is much greater than the length of the hydrodynamic and thermal initial sections. The case is investigated when the temperature changes along the channel. Channels of arbitrary cross-section (and, in particular, rectangular and circular) are considered. The situation is analyzed when the temperature changes along the channel, and this change is rather weak in relation to the temperature change along the channel walls (in the transverse direction, that is, in the plane of symmetry). To describe the state of the system, the so-called state diagram (dependence of the temperature on the axis of symmetry of the channel on the heat flux).
Źródło:
ECONTECHMOD : An International Quarterly Journal on Economics of Technology and Modelling Processes; 2020, 9, 2; 19--22
2084-5715
Pojawia się w:
ECONTECHMOD : An International Quarterly Journal on Economics of Technology and Modelling Processes
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
The effect of temperature-dependent viscosity and thermal conductivity on velocity and temperature field: an analytical solution using the perturbation technique
Autorzy:
Panahi-Kalus, H.
Ahmadinejad, M.
Moosaie, A.
Powiązania:
https://bibliotekanauki.pl/articles/38610956.pdf
Data publikacji:
2020
Wydawca:
Instytut Podstawowych Problemów Techniki PAN
Tematy:
temperature-dependent material properties
laminar channel flow
anaytical solution
perturbation technique
Opis:
This paper proposes a general form of the perturbation expansion method for the governing equations of viscous flow coupled to the temperature evolution. The effect of the variations of viscosity and thermal conductivity with temperature on the temperature and velocity fields in a steady two-dimensional Couette–Poiseuille flow is examined. The presented analytical solution by the perturbation method is validated against a finite difference solution of the governing equations. The numerical and analytical solutions are in good agreement.
Źródło:
Archives of Mechanics; 2020, 72, 6; 555-576
0373-2029
Pojawia się w:
Archives of Mechanics
Dostawca treści:
Biblioteka Nauki
Artykuł
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