Computational Analysis of Heat Transfer in Fluids and Solids II Edited by Prof. Oluwole Daniel Makinde Computational Analysis of Heat Transfer in Fluids and Solids II Special topic volume with invited peer-reviewed papers only Edited by Prof. Oluwole Daniel Makinde Copyright 2020 Trans Tech Publications Ltd, Switzerland All rights reserved. No part of the contents of this publication may be reproduced or transmitted in any form or by any means without the written permission of the publisher. Trans Tech Publications Ltd Kapellweg 8 CH-8806 Baech Switzerland http://www.scientific.net Volume 401 of Defect and Diffusion Forum ISSN print 1012-0386 ISSN cd 1662-9515 ISSN web 1662-9507 (Pt. A of Diffusion and Defect Data – Solid State Data ISSN 0377-6883) Full text available online at http://www.scientific.net Distributed worldwide by Trans Tech Publications Ltd Kapellweg 8 CH-8806 Baech Switzerland Phone: +41 (44) 922 10 22 Fax: +41 (44) 922 10 33 e-mail: [email protected] Preface Heat transfer and fluid flows seems to pervade all aspects of our life, since almost everything experiences heating or cooling of some kind and the entire life depends on fluid flows. Finding appropriate solutions to heat transfer problems in fluid and solid materials will enhance functional success of the materials and facilitate new product development in industries and engineering. This special issue on “Computational Analysis of Heat Transfer in Fluids and Solids II” in the journal “Defect and Diffusion Forum” addresses various nonlinear models involving heat transfer phenomenon in fluids and solids. Computational techniques are employed to analysis the problems and numerical results are discussed quantitatively in order to demonstrate the salient features of practical engineering and industrial applications. The topics covered by excellence research papers in this issue include: tribology, extended surfaces fins, reactive flow problem, Newtonian and non- Newtonian flow, nanofluids dynamics, boundary layer flow, natural convection, hydrodynamic stability, biomechanics, plasma physics, physics of dusty plasma, forced convection, mixed convection, magnetohydrodynamics, thermal radiation, porous media flow, and irreversibility analysis. The pertinent results obtained are very staple in understanding the complex interaction of heat transfer with fluids flow and solids mechanics. Wide range of applications of the work in this special issue can be found in the area of materials development, hydrodynamic lubrication, thermal storage, biomedical, solar heating, nuclear system cooling, micromixing technologies, military equipment storage, cooling of electrical and electronics components, product management, power production, pollution control and safety assessment. It is our hope that this special issue will inspire and help a wide audience of researchers, scientists, engineers and educators from various fields of human activity. Our appreciation goes to all the participants for their excellent contribution toward the success of this special issue. The outstanding work of the reviewers and their constructive comments are highly appreciated. Professor Oluwole Daniel Makinde Editor Table of Contents Preface A Study of Transient Heat Transfer through a Moving Fin with Temperature Dependent Thermal Properties L.P. Ndlovu and R.J. Moitsheki 1 Determination of Proper Fin Length of a Convective-Radiative Moving Fin of Functionally Graded Material Subjected to Lorentz Force G.A. Oguntala, G. Sobamowo, Y. Ahmed and R.A. Abd-Alhameed 14 A Note on the Similar and Non-Similar Solutions of Powell-Eyring Fluid Flow Model and Heat Transfer over a Horizontal Stretchable Surface R. Khan, M. Zaydan, A. Wakif, B. Ahmed, R.L. Monaledi, I.L. Animasaun and A. Ahmad 25 Biomechanics of Surface Runoff and Soil Water Percolation J.M.M. Deng and O.D. Makinde 36 Finite Element Numerical Investigation into Unsteady MHD Radiating and Reacting Mixed Convection Past an Impulsively Started Oscillating Plate B.P. Reddy, P.M. Matao and J.M. Sunzu 47 Analytical and Numerical Study on Cross Diffusion Effects on Magneto-Convection of a Chemically Reacting Fluid with Suction/Injection and Convective Boundary Condition S. Eswaramoorthi, M. Bhuvaneswari, S. Sivasankaran and O.D. Makinde 63 Physical Aspects on MHD Micropolar Fluid Flow Past an Exponentially Stretching Curved Surface K.A. Kumar, V. Sugunamma, N. Sandeep and S. Sivaiah 79 MHD Flow of Non-Newtonian Molybdenum Disulfide Nanofluid in a Converging/Diverging Channel with Rosseland Radiation J. Raza, F. Mebarek-Oudina, P. Ram and S. Sharma 92 Buoyancy Effects on Human Skin Tissue Thermoregulation due to Environmental Influence L.H. Adeola and O.D. Makinde 107 Turbulent Heat Transfer Characteristics of a W-Baffled Channel Flow - Heat Transfer Aspect Y. Menni, A.J. Chamkha and O.D. Makinde 117 MHD Boundary Layer Flow over a Cone Embedded in Porous Media with Joule Heating and Viscous Dissipation S. Devi and M.K. Sharma 131 Squeeze Film Lubrication on a Rigid Sphere and a Flat Porous Plate with Piezo-Viscosity and Couple Stress Fluid B.N. Hanumagowda, C.K. Sreekala, Noorjahan and O.D. Makinde 140 Influence of Homogeneous and Heterogeneous Chemical Reactions and Variable Thermal Conductivity on the MHD Maxwell Fluid Flow due to a Surface of Variable Thickness G. Sarojamma, K. Sreelakshmi, P.K. Jyothi and P.V.S. Narayana 148 Heat Transfer Analysis of Three-Dimensional Mixed Convective Flow of an Oldroyd-B Nanoliquid over a Slippery Stretching Surface K.V. Prasad, H. Vaidya, K. Vajravelu, G. Manjunatha, M. Rahimi-Gorji and H. Basha 164 Effects of Variable Fluid Properties on Oblique Stagnation Point Flow of a Casson Nanofluid with Convective Boundary Conditions H. Vaidya, K.V. Prasad, K. Vajravelu, A. Wakif, N.Z. Basha, G. Manjunatha and U.B. Vishwanatha 183 Defect and Diffusion Forum Submitted:2019-03-29 ISSN: 1662-9507, Vol. 401, pp 1-13 Revised:2019-06-14 © 2020 Trans Tech Publications Ltd, Switzerland Accepted:2019-09-18 Online:2020-05-28 A Study of Transient Heat Transfer Through a Moving Fin with Temperature Dependent Thermal Properties Partner Luyanda Ndlovu1,2,a and Raseelo Joel Moitsheki1,b,∗ 1School of Computer Science and Applied Mathematics, University of the Witwatersrand, Private Bag 3, WITS 2050, Johannesburg, South Africa 2Standard Bank of South Africa, 30 Baker Street, Rosebank, Johannesburg, 2196, South Africa [email protected], [email protected] Keywords: Heat transfer, analytical solutions, DTM, extended surface Abstract.Inthisarticle,heattransferthroughamovingfinwithconvectiveandradiativeheatdissipa tion is studied. The analytical solutions are generated using the twodimensional Differential Trans form Method (2D DTM) which is an analytical solution technique that can be applied to various types of differential equations. The accuracy of the analytical solution is validated by benchmark ing it against the numerical solution obtained by applying the inbuilt numerical solver in MATLAB (pdepe). A good agreement is observed between the analytical and numerical solutions. The effects of thermophysical parameters, such as the Peclet number, surface emissivity coefficient, power in dexofheattransfercoefficient,convectiveconductiveparameter,radiativeconductiveparameterand nondimensionalambienttemperatureonnondimensionaltemperatureisstudiedandexplained.Since numerousparametersarestudied,theresultscouldbeusefulinindustrialandengineeringapplications. Introduction Anincreasingnumberofengineeringapplicationsareconcernedwithenergytransportrequiringrapid heat dissipation. To increase the heat transfer rate from a heated surface, fin (or extended surface) assembly is commonly used. The use of fins is seen in various industrial applications such as oil carryingpipelines,spacenuclearreactorpowersystemsandmanymore.Theheattransfermechanism of a fin is to conduct heat from a heat source by thermal conduction, and then dissipate heat to an ambient fluid by the effect of thermal convection and radiation. An extensive review of extended surface heat transfer is given by Kern and Kraus [1] and Kraus et al. [2]. A brief review of published workthatisofrelevancetothisarticleispresentednext. A detailed study of temperature distribution in a moving fin is provided for various embedding parameters in a triangular fin [3], rectangular fin [4], an exponential fin [5] and a trapezoidal cross section[6].SinglaandDas[7]studiedaninverseproblemtoestimatethespeedofamovingfinusing the binarycoded generic algorithm. Sun et al. [8] applied the Spectral Collocation Method (SCM) to derivethesolutionforaconvectiveradiativeheattransferthroughamovingrodwithvariablethermal conductivity.SunandXu[9]furtherappliedtheSCMtopredictthetemperaturedistributioninmoving finsofcomplexcrosssections.Recently,Maetal.[10]simulatedacombinedconductive,convective andradiativeheattransferinirregularmovingporousfinsusingSpectralElementMethod(SEM).In vestigation of mixed convection heat transfer along a continuously moving heated vertical plate with suctionandblowingwasconductedbyAlSanea[11].Theradiationeffectsarequitesignificantinvar iousengineeringandindustrialprocessesespeciallyinthedesignofreliableequipments,nuclearplants and gas turbines. Razelos and Kakatsios [12] investigated the optimum dimensions of convecting radiating rectangular fins. They studied the influence of all dependent parameters on optimization and performance of rectangular fins. They also investigated the effect of the temperaturedependent thermal conductivity and emissivity on the temperature profile. An approximate analytical solution for convectionradiation heat transfer from a continuously moving fin with temperaturedependent thermalconductivitywasdevelopedbyAzizandKhani[13].TorabiandZhang[14]investigatedther mal performance of a convectiveradiative straight fin by considering different profiles containing 2 Computational Analysis of Heat Transfer in Fluids and Solids II nonlinearities and further studied the fin efficiency. Sun et al. [15] studied the different temperature dependentthermalpropertiesforpredicationofheattransferinaconvectiveradiativefin.Kunduand Wongwises [16] presented a decomposition analysis of a convectiveradiating fin with one side of the primary surface being heated by a fluid with high temperature. Aziz and Makinde [17] applied a twodimensional heat conduction model to obtain the thermal performance and entropy generation in an orthotropic convection pin fin used in advanced light weight heat sinks. The study illustrated thesimultaneousrealizationoftheleastmaterialandminimumentropygenerationinpinfindesigns. Mhlongo et al. [18] applied the local and nonlocal symmetry techniques to study transient response ofrectangularfinstostepchangeinbasetemperatureandbaseheatflux.Theauthorsshowedthatthe governingequationscanbereducedtothetractableErmakovPinneyequation. The DTM is a seminumericalanalytical method based on the Taylor series expansion and was firstproposedbyZhou[19]in1986forthesolutionoflinearandnonlinearinitialvalueproblemsthat appear in the analysis of electrical circuits. This method was subsequently used to obtain analytical solutions of various types of higherorder differential equations. Torabi et al. [20] applied the DTM to derive approximate explicit analytical expressions for the temperature distribution in a moving fin withtemperaturedependentthermalconductivityandexperiencingsimultaneousconvectiveradiative surface heat loss. Moradi and Rafiee [21] extended the work of Torabi et al. to study a similar model for various fin profiles. Ndlovu and Moitsheki [22] successfully applied the 2D DTM to a transient heatconductionproblemforheattransferinlongitudinalrectangularandconvexparabolicfins.Some interestingresultswereobtainedandtheeffectsoftheparametersappearinginthemodelonthetem perature distribution were illustrated and explained. Mosayebidorcheh et al. [23] studied transient thermal behavior of radial fins of rectangular, triangular and hyperbolic profiles. These authors ap plied the Hybrid Differential Transform MethodFinite Difference Method (DTMFDM) to generate thenumericalsolutionstotheproblem.Falloetal.[24]appliedthe3DDTMforthefirsttimetostudy heat transfer in a cylindrical spine fin with variable thermal properties. Hatami et al. [25] applied the Differential Quadrature Method (DQM) together with the DTM to study magnetohydrodynamic (MHD)twophaseCouetteflowanalysisforfluidparticlesuspensionbetweenmovingparallelplates. To the best our knowledge, no research to date has been performed to study transient heat transfer in amovingfins.Numerousstudieshavebeendevotedtosteadystateanalysiswiththeassumptionthat thetransientresponsediesoutquickly[26,27]. In this article, 2D DTM is applied to study simultaneous conductive, convective and radiative heattransferinamovingfinofrectangularprofile.Thermalconductivity,heattransfercoefficientand surface emissivity are all temperature dependent. The problem formulation is presented in Section 2. Abriefdiscussiononthefundamentalsofthe2DDTMisprovidedinSection3.Thevalidationofthe analytical solutions together with analytical results are given in Section 4. Lastly, we provide some discussionsbasedontheresultsobtainedinSection5andtheconclusionssummarizedareSection6. ProblemFormulation We consider a one dimensional rectangular moving fin of length L, with crosssectional area A , c thickness δ and perimeter P while it moves horizontally with a constant velocity U as depicted in Figure 1. The fin surface is exposed to a convective and radiative environment of temperature T a and the base temperature of the fin is T > T . The fluid surrounding the moving fin is heated by b a theconvectiveradiativefinandinducesahorizontalflowfield(advection).Theradiativecomponent wouldbemoreprominentiffinundergoesnaturalconvectionoriftheforcedconvectionisratherweak orabsent.Theenergybalanceequationforthemovingfinlosingheatbysimultaneousconvectionand radiationcanbeexpressedas (cid:20) (cid:21) ∂T ∂ ∂T PH(T) Pσε(T) ∂T ρc = K(T) − (T −T )− (T4 −T4)−ρcU , 0 ≤ X ≤ L. (1) ∂t ∂X ∂X A a A a ∂X c c Defect and Diffusion Forum Vol.401 3 Formostmaterials,thethermalconductivityvarieslinearlywithtemperature,thatis, K(T) = k [1+γ(T −T )], (2) a a thesurfaceemissivityisalsoassumedtovarylinearlywithtemperature, ε(T) = ε [1+η(T −T )], (3) a a andheattransfercoefficientmaybegivenbyapowerlawfunctionoftemperature, (cid:18) (cid:19) T −T n a h(T) = h . (4) b T −T b a Fig. 1:Schematicrepresentationofarectangularmovingfin. Here, k is the thermal conductivity of the fin at ambient temperature, γ is a measure of thermal a conductivityvariationwithtemperature,ε isthesurfaceemissivityofthefinatambienttemperature, a η is a measure of surface emissivity variation with temperature, ρ is the density of fluid; c is the specific heat of fluid; ε and σ are the emissivity and Boltzman constant respectively, h is the heat b transfer coefficient at the fin base and n is a constant. The constant n may vary between 6.6 and 5. However, in most practical applications it lies between 3 and 3 [28]. The exponent n represents laminar film boiling or condensation when n = −1/4, laminar natural convection when n = 1/4, turbulent natural convection when n = 1/3, nucleate boiling when n = 2, radiation when n = 3 and n = 0 implies a constant heat transfer coefficient. Assuming that the fin tip is adiabatic (insulated) andthebasetemperatureiskeptconstant,thentheboundaryconditionsaregivenby[2]etal., T(t,L) = T and (5) (cid:12) b (cid:12) ∂T (cid:12) (cid:12) = 0. (6) ∂X X=0 Initiallythefiniskeptattheambienttemperature, T(0,X) = T . (7) a 4 Computational Analysis of Heat Transfer in Fluids and Solids II Introducingthefollowingdimensionlessvariables, X k t T T a a x = , τ = , θ = , θ = , ζ = ηT , β = γT , L ρcL2 T a T b b b b (8) Ph TnL2 Pε σL2T3 k UL N = b b , N = a b , α = a, andPe = , c k A (T −T )n r k A ρc α a c b a a c reducestheenergyequation(1)to (cid:20) (cid:21) ∂θ ∂ ∂θ = {1+β(θ−θ )} −N (θ−θ )n+1 −N [1+ζ(θ−θ )](θ4 −θ4) ∂τ ∂x a ∂x c a r a a ∂θ −Pe , 0 ≤ x ≤ 1. (9) ∂x Theprescribedboundaryconditionsaregivenby, θ(τ,1) = 1and (10) (cid:12) (cid:12) ∂θ(cid:12) (cid:12) = 0. (11) ∂x x=0 andtheinitialconditionbecomes, θ(0,x) = 0. (12) Thedimensionlessvariableθrepresentsthetemperature,θ representsthedimensionlessambienttem a perature, x is the dimensionless space variable, τ is the dimensionless time variable, β is the thermal conductivitygradient,ζ isthesurfaceemissivitygradient,N istheconvectionconductionparameter, c N istheradiationconductionparameter,PeisthePecletnumberwhichrepresentthedimensionless r speedofthemovingfin,α isthethermaldiffusivityofthefin. FundamentalsoftheTwoDimensionalDifferentialTransformMethod In this section, the basic idea underlying the twodimensional DTM is briefly introduced. If function θ(t,x)isanalyticanddifferentiatedcontinuouslywithrespecttotimeandthespatialvariablexinthe domainofinterest,thenwelet (cid:20) (cid:21) 1 ∂κ+sϕ(t,x) Φ(κ,s) = , (13) κ!s! ∂tκ∂xs (0,0) where the spectrum Φ(κ,s) is the transformed function, which is also called the Tfunction (see [29, 30]).ThedifferentialinversetransformofΦ(κ,s)isdefinedas X∞ X∞ ϕ(t,x) = Φ(κ,s)tκxs, (14) κ=0 s=0 andfromequations(13)and(14)itcanbeconcludedthat (cid:20) (cid:21) X∞ X∞ 1 ∂κ+sϕ(t,x) ϕ(t,x) = tκxs. (15) κ!s! ∂tκ∂xs κ=0 s=0 (0,0)