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1

The application of the Wilson plot method to convective heat transfer - last achievements

Tychanicz-Kwiecień Maria

Zeszyty Naukowe Politechniki Rzeszowskiej. Mechanika

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2022

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z. 94

77--89

EN

The paper discusses and presents the application of the Wilson plot method to the variety of issues related to convective heat transfer. The Wilson plot is a remarkable calculation procedure, which enables the analysis and estimation of convection heat transfer coefficient on the basis of experimental measurements of heat exchanger thermal and flow parameters and the evaluation of corresponding correlation equations. The main facility of the Wilson method is that the heat transfer coefficient can be obtained without the requirement of determining the surface temperature. Much attention was paid to clarify the concept of the standard, original Wilson method as well as its modified versions. The issue was presented in the form of the latest literature review, which featured the investigation of convection coefficients obtained by the Wilson method in the following cases: the flow of nanofluids, refrigerants and other working media in conventional and mini/micro channels and micro-tubes as well as heat transfer under boiling/condensation conditions. The validity of the method utilization has been presented and its future prospects have been specified.

PL

W artykule omówiono i przedstawiono zastosowanie metody Wilsona w różnorodnych zagadnieniach związanych z wymianą ciepła na drodze konwekcji. Metoda Wilsona pozwala na analizę i określenie konwekcyjnego współczynnika przejmowania ciepła na podstawie eksperymentalnych pomiarów parametrów cieplnych i przepływowych badanego wymiennika ciepła oraz zastosowanie lub opracowanie odpowiednich zależności korelacyjnych. Szczególnym atutem metody Wilsona jest możliwość określenia współczynnika przejmowania ciepła bez konieczności pomiaru temperatury powierzchni badanego wymiennika ciepła Dużo uwagi poświęcono wyjaśnieniu koncepcji standardowej, oryginalnej metody Wilsona oraz jej zmodyfikowanych wersji. Zagadnienie zostało przedstawione w formie przeglądu literatury, w którym uwzględniono podsumowanie wyników badań współczynników przejmowania ciepła uzyskanych metodą Wilsona w następujących przypadkach: przepływu nanocieczy, czynników chłodniczych i innych mediów roboczych w kanałach konwencjonalnych i mini/mikrokanałach oraz mikrorurkach, jak również wymianę ciepła podczas wrzenia/kondensacji. Przedstawiono zasadność wykorzystania metody oraz określono jej perspektywy na przyszłość.

2

The influence of geometric characteristics of the buildings facades on the heat transfer to the wind flow

Basok Boris, Davydenko Boris, Pavlenko Anatoliy, Novikov Vladimir, Novitska Marina

Journal of New Technologies in Environmental Science

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2021

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Vol. 5, nr 1

11--22

EN

This paper presents the results of a numerical study of heat transfer from the external surfaces of freestanding structures in the surface layer of the atmosphere. Numerical models of structures have the same heat transfer area, but different heights and lengths. Numerical modeling of heat transfer from structures in a wind flow in a three-dimensional formulation made it possible to establish some features of convective heat transfer from enclosing structures, depending on the height of the building and the speed of the wind flow. In particular, it is shown that the dependence of the surface-averaged values of the heat flux density on the height of the building has a local minimum, after which the average heat flux density increases insignificantly with an increase in the height of the building.

3

Effects of pressure gradient on convective heat transfer in a boundary layer flow of a Maxwell fluid past a stretching sheet

Kashif A. N., Salah F., Sankar D. S., Izyan M. D. N., Viswanathan K. K.

International Journal of Applied Mechanics and Engineering

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2021

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Vol. 26, no. 3

104--118

EN

The pressure gradient term plays a vital role in convective heat transfer in the boundary layer flow of a Maxwell fluid over a stretching sheet. The importance of the effects of the term can be monitored by developing Maxwell’s equation of momentum and energy with the pressure gradient term. To achieve this goal, an approximation technique, i.e. Homotopy Perturbation Method (HPM) is employed with an application of algorithms of Adams Method (AM) and Gear Method (GM). With this approximation method we can study the effects of the pressure gradient [...], Deborah number [...], the ratio of the free stream velocity parameter to the stretching sheet parameter [...] and Prandtl number [...] on both the momentum and thermal boundary layer thicknesses. The results have been compared in the absence and presence of the pressure gradient term m. It has an impact of thinning of the momentum and boundary layer thickness for non-zero values of the pressure gradient. The convergence of the system has been taken into account for the stretching sheet parameter. The result of the system indicates the significant thinning of the momentum and thermal boundary layer thickness in velocity and temperature profiles.

4

Efficient simulations of large-scale convective heat transfer problems

Goik Damian, Banaś Krzysztof, Bielański Jan, Chłoń Kazimierz

Computer Science

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2021

|

T. 22 (4)

517--538

EN

We describe an approach for efficient solution of large-scale convective heat transfer problems that are formulated as coupled unsteady heat conduction and incompressible fluid-flow equations. The original problem is discretized over time using classical implicit methods, while stabilized finite elements are used for space discretization. The algorithm employed for the discretization of the fluid-flow problem uses Picard’s iterations to solve the arising nonlinear equations. Both problems (the heat transfer and Navier–Stokes equations) give rise to large sparse systems of linear equations. The systems are solved by using an iterative GMRES solver with suitable preconditioning. For the incompressible flow equations, we employ a special preconditioner that is based on an algebraic multigrid (AMG) technique. This paper presents algorithmic and implementation details of the solution procedure, which is suitably tuned – especially for ill-conditioned systems that arise from discretizations of incompressible Navier–Stokes equations. We describe a parallel implementation of the solver using MPI and elements from the PETSC library. The scalability of the solver is favorably compared with other methods, such as direct solvers and the standard GMRES method with ILU preconditioning.

5

Numerical investigation of convective heat transfer of single wall carbon nanotube nanofluid laminar flow inside a circular tube

Saeed Farqad Rasheed, Jasim Marwah A., Mahmood Natheer B., Jaffar Zahraa M.

Archives of Thermodynamics

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2021

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Vol. 42, no 2

103--119

EN

This study presents the behavior of a single wall carbon nanotube (SWCNT)/water nanofluid for convective laminar flow inside a straight circular pipe heated by a constant heat flux. Five volume fractions of SWCNT were used to investigate their effect on the heat transfer coefficient, Nusselt number, temperature distribution and velocity field in comparison with pure water flow. One model for each property was tested to calculate the effective thermal conductivity, effective dynamic viscosity, and effective specific heat of the SWCNT/water mixture. The models were extracted from experimental data of a previous work. The outcomes indicate that the rheological behavior of SWCNT introduces a special effect on the SWCNT/water properties, which vary with SWCNT volume fraction. The results show an improvement in the heat transfer coefficient with increasing volume fraction of nanoparticles. The velocity of SWCNT/water nanofluid increased by adding SWCNT nanoparticles, and the maximum increase was registered at 0.05% SWCNT volume fraction. The mixture temperature is increased with the axial distance of the pipe but a reduction in temperature distribution is observed with the increasing SWCNT volume fraction, which reflects the effect of thermophysical properties of the mixture.

6

Numerical investigation for convective heat transfer of nanofluid laminar flow inside a circular pipe by applying various models

Saeed Farqad Rasheed, Al-Dulaimi Marwah Abdulkareem

Archives of Thermodynamics

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2021

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Vol. 42, no 1

71--95

EN

The work presents a numerical investigation for the convective heat transfer of nanofluids under a laminar flow inside a straight tube. Different models applied to investigate the improvement in convective heat transfer, and Nusselt number in comparison with the experimental data. The impact of temperature dependence, temperature independence, and Brownian motion, was studied through the used models. In addition, temperature distribution and velocity field discussed through the presented models. Various concentrations of nanoparticles are used to explore the results of each equation with more precision. It was shown that achieving the solution through specific models could provide better consistency between obtained results and experimental data than the others.

7

Analysis of selected aspects of a tank gassing-up process on board liquefied petroleum gas carrier. Part I

Wieczorek Agnieszka

Archives of Thermodynamics

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2021

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Vol. 42, no 2

43--58

EN

The paper is a thermodynamics analysis of the removal of any inert gas from the tank using the vapors of any liquefied petroleum gas cargo (called cargo tank gassing-up operation). For this purpose, a thermodynamic model was created which considers two boundary cases of this process. The first is a ‘piston pushing’ of inert gas using liquefied petroleum gas vapour. The second case is complete mixing of both gases and removal the mixture from the tank to the atmosphere until desired concentration or amount of liquefied petroleum gas cargo in the tank is reached. Calculations make it possible to determine the amount of a gas used to complete the operation and its loss incurred as a result of total mixing of both gases.

8

Modelling of thermoelastic transient contact interaction for binary bearing taking into account convection

Kolesnikov I., Danilchenko S., Kolosova E., Chebakov M., Lyapin A.

Transport Problems

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2016

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T. 11, z. 4

73--81

EN

Serviceability of metal-polymeric "dry-friction" sliding bearings depends on many parameters, including the rotational speed, friction coefficient, thermal and mechanical properties of the bearing system and, as a result, the value of contact temperature. The objective of this study is to develop a computational model for the metallic-polymer bearing, determination on the basis of this model temperature distribution, equivalent and contact stresses for elements of the bearing arrangement and selection of the optimal parameters for the bearing system to achieve thermal balance. Static problem for the combined sliding bearing with the account of heat generation due to friction has been studied in [1]; the dynamic thermoelastic problem of the shaft rotation in a single and double layer bronze bearings were investigated in [2, 3].

RU

Работоспособность полимерных подшипников скольжения «сухого трения» зависит от многих параметров, включающих в себя скорость вращения вала, коэффициент трения, термо-механические свойства элементов подшипниковой системы и, как следствие, величины результирующих контактных температур. Целью данного исследования является разработка расчётной модели работы бинарного подшипника скольжения «сухого трения» с полимерными цилиндрическими вставками, определения на ее основе распределения температур, эквивалентных и контактных напряжений в элементах подшипниковой системы и подбор оптимальных параметров подшипниковой системы, при которых достигается тепловой баланс. Статическая задача для комбинированного подшипника скольжения с учётом тепловыделения от трения была исследована в работе [1], динамическая термоупругая задача о вращении вала в однослойном подшипнике из бронзы была исследована в работе [2], двухслойного с антифрикционным покрытием в.

9

Influence of Axial Heat Conduction in the Wall on Convective Heat Transfer in the Microchannel

Mikielewicz J., Rybiński W.

Rocznik Ochrona Środowiska

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2015

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Tom 17, cz. 1

82--89

PL

Opracowany został nowy model umożliwiający obliczenie wpływu podłużnego przewodzenia ciepła w ściance kanalika na wymianę ciepła pomiędzy ścianką a przepływającym czynnikiem w mikrokanale. Zbadany został przypadek ustalonej wymiany ciepła. Znaleziono bezwymiarowe kryterium umożliwiające ocenę ważności wzdłużnego przewodzenia ciepła w ściance. W publikacji przedstawiono porównanie wyników modelu z wynikami przy zaniedbaniu podłużnego przewodzenia ciepła oraz z wynikami innego modelu opracowanego przez Kandlikara. Dodatkowo wykonano porównanie nowego modelu z wynikami eksperymentalnymi innych autorów. Osiągnięto zadawalające rezultaty.

10

Numerical Study of the Effect of a Natural Convective Boundary Layer around the Human Body on the Transfer of Heat through a Textile Structure

Angelova R. A., Stankov P., Kyosov M.

Fibres & Textiles in Eastern Europe

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2015

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Vol. 23, no. 6 (114)

131--137

EN

Heat losses from the human body occur through a barrier of one or more textile layers with particular permeability, thermal insulation, water absorption abilities, etc. The convective boundary layer (CBL) around the clothed body is disturbed during body movement, and the air layer between the body and the textile layer(s) is broken up, thus changing the heat transfer through the textile layer and its insulation abilities. The purpose of the present study was to evaluate the effect of the convective boundary layer around the human body on the heat transfer through a textile layer by numerical simulation, using Computational Fluid Dynamics and a commercial CFD software package, by means of the Finite Volume Method. A new approach for modeling a textile surface was applied based on the theory of jet systems. The results of the study indicated that heat transfer trough the textile barrier is strongly influenced by the speed of the convective layer around the human body and the textile layer placed in between the body and the environment.

PL

Straty ciepła ciała ludzkiego występują poprzez barierę utworzoną z jednej lub więcej warstw tekstylnych o określonej przepuszczalności, termicznej, izolacyjności, zdolności absorpcji wody itd. Konwekcyjna warstwa graniczna wokół ubranego ciała zakłócana jest podczas ruchu tego ciała i warstwy powietrza pomiędzy ciałem i warstwą tekstylną, która może być przerwana i zmienić przepływ ciepła poprzez warstwę tekstylną, a tym samym właściwości izolacyjnych. Celem prezentowanych badań była ocena wpływu granicznej warstwy konwekcyjnej wokół ciała na przepływ ciepła za pomocą numerycznej symulacji przy zastosowaniu odpowiednich programów komputerowych i metody elementów skończonych. Zastosowano nową próbę modelowania powierzchni włókienniczej opartą na teorii systemów dysz. Wyniki badań wykazały, że przepływ ciepła przez bariery tekstylne ulega silnym wpływom prędkości powietrza w warstwie wokół ciała ludzkiego i pomiędzy warstwami tekstylnymi.

11

Convective heat transfer for fluids passing through aluminum foams

Dyga R., Troniewski L.

Archives of Thermodynamics

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2015

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Vol. 36, no. 1

139--156

EN

This paper analyses the experimental findings within heat transfer when heating up air, water and oil streams which are passed through a duct with internal structural packing elements in the form of metal foams. Three types of aluminum foams with different cell sizes, porosity specifications and thermal conductivities were used in the study. The test data were collected and they made it possible to establish the effect of the foam geometry, properties of fluids and flow hydrodynamic conditions on the convective heat transfer process from the heating surface to the fluid flowing by (wetting) that surface. The foam was found to be involved in heat transfer to a limited extent only. Heat is predominantly transferred directly from the duct wall to a fluid, and intensity of convective heat transfer is controlled by the wall effects. The influence of foam structural parameters, like cell size and/or porosity, becomes more clearly apparent under laminar flow conditions.

12

Numerical heat transfer in a rectangular channel with mounted obstacle

Gareh S.

International Letters of Chemistry, Physics and Astronomy

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2014

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Vol. 19, iss. 2

111--119

EN

The fully-incompressible, viscous and stationary Navier–Stokes equations are solved for the laminar flow over an obstacle placed on the lower of a channel. The Reynolds number is varied from 100 to 400. In all cases studied the flow field proves to be steady. Several distinct flow features are identified: a horseshoe vortex system, inward bending flow at the side walls of the obstacle, a horizontal vortex at the downstream lower-half of the obstacle and a downstream wake containing two counter-rotating vortices. The shape and size of these flow features are mainly dominated by the Reynolds number. For higher Reynolds numbers, both the horseshoe vortex and the wake region extend over a significantly larger area. The correlation of the position of the separation and attachment point with the Reynolds number has been calculated. A detailed analysis is carried out to investigate flow pattern and Nusselt number.

13

Zastosowanie metody z wykorzystaniem anemometrycznych sond foliowych do analizy procesów konwekcyjnego przepływu ciepła

Górska M.

Hutnik, Wiadomości Hutnicze

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2013

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Vol. 80, nr 5

395--397

PL

W artykule przedstawiono wyniki badań eksperymentalnych wnikania ciepła podczas chłodzenia walca zaburzonym pulsacyjnie strumieniem powietrza. Pomiary prowadzono podczas przepływu pulsacyjnego oraz przepływu niezmiennego w czasie w komorze aerodynamicznej, w której umieszczono walec, o średnicy 78 mm, w płaszczyźnie poziomej przechodzącej przez oś komory. Na powierzchni walca zainstalowano dwie stałotemperaturowe anemometryczne sondy foliowe. Metodyka pomiaru opierała się na bilansie energii pobranej przez strumień przepływającego powietrza oraz energii doprowadzonej do sondy w celu utrzymania stałej temperatury włókna. Ilości energii pobranej na zasadzie konwekcji przez przepływające powietrze określano jako różnicę średniej wartości napięcia i wartości napięcia wyjściowego (bez przepływu).

EN

In the article some results of experimental researches of penetrating heat during the cooling cylinder that is pulsatory disturb by air flow were presented. Measurements were conducted during the pulsating flow and the unchanging flow in the time. In the aerodynamic chamber was put the cylinder, with the diameter 78mm, in the horizontal plane which was covered through the axis chambers. On the surface of the cylinder were installed two permanent-temperature anemometer foil probes. The methodology of the measurement was based on balance of the energy taken by the stream of flowing air and the energy supplied to the probe in the purpose of holding the constant temperature of fibre. The amounts of the energy taken on the principle of the convection through flowing air were determined as the difference of tension average value and value of the initial tension (without the flow).

14

Wpływ udziału faz na wnikanie ciepła przy przepływie dwufazowym przez struktury siatkowe

Dyga R.

Inżynieria i Aparatura Chemiczna

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2009

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Nr 6

51-52

PL

Przedstawiono wyniki badań przepływu powietrze — woda przez ogrzewane kanały z wypełnieniem siatkowym. Określono strumień wymienianego ciepła oraz współczynnik wnikania ciepła przy przepływie dwufazowym przez kanał całkowicie oraz częściowo wypełniony. Stwierdzono silny wpływ sposobu wypełnienia kanału na transport ciepła oraz dominującą rolę cieczy w nieadiabatycznym przepływie gaz-ciecz przez wypełnienie siatkowe.

EN

Experimental findings for air - water flow through heated channels with a wire mesh packing are presented in the paper. The heat flux and heat transfer coefficient were determined under two-phase flow conditions through a full and partly filled channel. A strong influence of channel packing method on heat transfer and prevailing role of liquid phase in non-adiabatic gas - liquid flow through the meshed packing were stated.

15

On the accuracy of the finite element solution to the steady state convection-diffusion heat transport equation in the continues steel casting problem

Hadala B., Malinowski Z.

Computer Methods in Materials Science

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2009

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Vol. 9, No. 2

302-308

EN

The steady state convection-diffusion equation plays an important role in description of the heat transfer in many technical problems. Finite element method is widely used to solve such problems. However, in convection dominated problems oscillatory solutions to the temperature field have been observed. Several methods have been proposed to overcame these difficulties. One of the method is known as an upwind finite element scheme [1], other possibilities have been presented In [2]. It has been shown in [3] that in some cases upwind finite element scheme does not give any reasonable results [3]. Transient solutions give satisfactory results, however the computational time is high and in the case of three dimensional problems difficult to accept. The problem is much more complicated because good looking results may give substantial error in the temperature field determination. In the paper the accuracy of several finite element solutions to the heat transfer in the continues steel casting problem have been discussed. The heat balance in the control volume has been computed in order to assess the solutions accuracy. It turned out that Galerkin method gives solutions that may miss the heat balance by 20%. New variational formulation has been proposed to solve steady state convection-diffusion equation. The method uses Hermitian shape function and second order derivatives to the temperature field.

PL

Równanie ustalonego stanu konwekcja-dyfuzja odgrywa ważną rolę w opisie wymiany ciepła w wielu problemach technicznych. Wśród metod numerycznych, umożliwiających rozwiązanie powyższego równania, szerokie zastosowanie znalazła metoda elementów skończonych. Jednakże rozwiązanie równania w warunkach konwekcji w przypadku metody elementów skończonych nie zawsze pozwala uzyskać stabilne rozwiązania. Zaobserwowano wyniki oscylujące wokół temperatury powierzchni. Tego typu problemy próbowano pokonać poprzez zastosowanie odpowiedniej metody. Przejściowe rozwiązania pozwoliły uzyskać satysfakcjonujące wyniki, jednakże czas obliczeniowy okazał się długi i w przypadku trójwymiarowych zagadnień trudny do zaakceptowania. Jednym z istotnych problemów przy doborze odpowiedniej metody są poprawnie zinterpretowane wyniki obliczeń. Niejednokrotnie pozornie dobrze wyglądające wyniki pola temperatury są obarczone istotnym błędem. W pracy oszacowano bilans cieplny w kontrolowanej objętości w procesie ciągłego odlewania stali. Przeprowadzono dyskusję oceny dokładności rozwiązania równania ustalonego stanu konwekcja-dyfuzja przy zastosowaniu wybranych metod opartych o elementy skończone. Zaproponowano nowe wariacyjne sformułowanie umożliwiające rozwiązanie powyższego równania. W metodzie zastosowano funkcje kształtu Hermite'a.

16

Estimation of the influence of inflow turbulence on heat convection from a sphere surface

Bogusławski L.

Journal of Theoretical and Applied Mechanics

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2007

|

Vol. 45 nr 3

505-511

EN

In the paper, results of an experimental investigation of a heat transfer coefficient on a sphere for different inflow turbulence levels have been presented. The average heat transfer coefficient on the sphere surface appear to be dependent on the turbulence level of flow around the sphere. This effect of influence of the flow structure near the sphere surface on the heat transfer process have been presented. Distributions of heat transfer on spheres of different diameters for different turbulence levels of the inflow have been analyzed. It has been shown that an increase of the inflow turbulence level caused an increase of the average heat transfer coefficient on the sphere surface. The maximum increase of the heat transfer due to growing turbulence has been found to be about 30%.

PL

W pracy przedstawiono wyniki badań eksperymentalnych współczynników przejmowania ciepła na kuli przy różnych stopniach turbulencji napływającej strugi. Średni współczynnik przejmowania ciepła na powierzchni kuli jest zależny od stopnia turbulencji przepływu wokół kuli. Jest to rezultat zmiany struktury przepływu w pobliżu ścianki kuli wpływającej na procesy transportu ciepła. Przeprowadzono analizę wymiany ciepła na kulach o różnych średnicach przy zmianie stopnia turbulencji napływającej strugi. Wzrost stopnia turbulencji napływu powoduje wzrost średniego współczynnika przejmowania ciepła na powierzchni kuli. Maksymalny wzrost wymiany ciepła spowodowany wzrostem turbulencji przepływu był rzędu 30%.

17

A theoretical study of heat transfer to flowing granular materials

Massoudi M., Anand N. K.

International Journal of Applied Mechanics and Engineering

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2004

|

Vol. 9, no 2

383-398

EN

The mechanics of flowing granular materials such as coal, sand, agricultural products, fertilizers, dry chemicals, metal ores, etc., and their flow characteristics have received considerable attention in recent years. In a number of instances these materials are also heated prior to processing or cooled after processing. In this paper, the governing equations for the flow of granular materials, taking into account the heat transfer mechanism are derived using a continuum model proposed by Rajagopal and Massoudi (1990). For a fully developed flow down a heated inclined plane, the governing equations reduce to a system of non-linear ordinary differential equations for the case where the material properties are assumed to be constants. The boundary value problem is solved numerically and the results are presented for the volume fraction, velocity, and temperature profiles.

18

Experimental investigation of the convective heat transfer around a perpendicular plate by means of flow visualization techniques

Błaszczuk A., Mirek P.

Archives of Thermodynamics

|

2004

|

Vol. 25, no. 3

73-86

EN

The subject of the study is presentation of optical techniques for the measurement of local values of overall heat transfer coefficient. Measuring systems based on Schlieren and interference systems, built either in classical versions or modified by the authors of the present study, were used in the research. The recording of the distribution of optical density of the information carrier around the object under analysis was carried out using a CCD matrix with the image acquisition card. The role of the information carrier in the experimental research was performed, alternatively, by the collimated beam of a 25 mW-power He-Ne laser or a slotted white light source in the form of a halogen lamp, type H3. The modifications introduced to the optical measuring range along with a reduction in the susceptibility of the systems to misalignment.

19

Transient laminar-turbulent transition of thermal boundary layer after the change of incidence angle

Wierciński Z., Kaiser M.

Transactions of the Institute of Fluid-Flow Machinery

|

2003

|

nr 114

237-252

EN

Convective heat transfer problems occur in many technical application. Unsteady transition in the heated boundary layer is one of them. Heat transfer investigation of a flat plate in a low subsonic wind tunnel for flow velocity Uo=15 and 20 m/s was performed. The changes in time of the Stanton number distribution along the plate were observed after the incidence angle had been changed from - 0.8 to 0°. While for the incidence angle i= -0.8° the flow in boundary layer was laminar, for angle -0.67#176 the transition was observed, and for the angle -0.23° the flow was turbulent. After the sudden change of angle the transient bahaviour of the heat transfer between these three states were observed, e.g. for the change from -0.8 to -0.6° from laminar to transitional, so after the time of about 30 min the transition was perfect. This time is needed to achieve a new internal thermal balance of the plate and transition in thermal boundary is established.

20

Quantitative infrared thermography and convective heat transfer measurements

Carlomagno G. M.

Machine Graphics and Vision

|

1999

|

Vol. 8, No. 4

509-528

EN

When using infrared thrmography to perform convective heat transfer measurements, it is necessery to restore the thermal images because of thier degradation which is due to the heat flux sensor, the environment and the temperature sensor. This problem is addressed herein. Besides, infrared thermography is employed to study three different fluid flow configurations ; in particular: the heat transfer to a jet centrally impinging on a rotating disk; the complex heat transfer pattern associated with a jet in cross-flow ; the heat transfer distribution along 180° turn channel. Attention is focused on the capability of the infrared thermography to deal with complex flow dynamics, the interaction between the jet and the boundary layer linked to the disk rotation, heat transfer developing in the wake region of a jet in cross-flow, high heat transfer regions and recirculation bubbles in a 180° turn channel.