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Heat transfer characteristics of the traditional wall jet flows subject to various thermal boundary conditions including isothermal surface, prescribed temperature, constant heat flux, prescribed heat flux, adiabatic surface and thermally convective surface are documented in analytic closed forms. Heat dissipation has been also included where the similarity energy equation could structurally adjust to this specific term (for the adiabatic case, this term has been necessarily included). In all the studied cases, both the transpiration velocity and moving wall conditions are allowed to exist (where applicable) in such a way, being consistent with the Glauert integral constraint and subject to the context of exponentially decaying wall jet flows. In particular, it is analytically proved (even without having the closed form solutions) that for the Glauert original case, a surface with a prescribed temperature in the form of T w ( x ) = m x − 1 4 + T ∞ serves zero contribution to heat transfer at the wall (the Induced Heat Shield). More precisely, the value − 1 4 as the prescribing parameter is the Surface Heat Transfer Stopping Point and below this point, heat transfer phenomenon falls from a usual physical interpretation, expressing spectrums of thermal instabilities through a hyper geometric function. Furthermore, it is argued that a normalized similarity temperature in the form of θ ( η ) = T − T ∞ m x n < − 1 4 results in the appearance of an uninterruptable singularity within the heat transfer phenomenon for the Glauert case subject to a rigorous physical ground; and as an immediate practical consequence, there is no physically-valid similarity solution for an adiabatic surface or more precisely, for energy equation with heat dissipation consideration. It should be mentioned that the concept of Induced Heat Shield is discussed in here for the first time (to our knowledge) which may inspire a concealed fact regarding the restrictions of the thermal similarity solutions. Therefore, it is hopeful that heat transfer phenomenon in the Glauert type wall jet flows and the associated physical representations can be better understood by the present research. [ABSTRACT FROM AUTHOR]

The purpose of present study is to identify the effects of viscous dissipation and suction/injection on MHD flow of a nanofluid past a wedge with convective surface in the appearance of slip flow and porous medium. The basic non-linear PDEs of flow and energy are altered into a set of non-linear ODEs using auxiliary similarity transformations. The system of equations together with coupled boundary conditions have been solved numerically by applying Runge-Kutta-Fehlberg procedure via shooting scheme. The influence of relevant parameters on non-dimensional velocity and temperature profiles are depicted graphically and investigated in detail. The results elucidate that as enhance in the Eckert number, the skin friction coefficient increases, while heat transfer rate decreases. The outcomes also specify that thermal boundary layer thickness declines with an increase in suction parameter. Moreover, it is accelerated with augment in injection parameter. The results are analogized with the study published earlier and it creates a fine concord. [ABSTRACT FROM AUTHOR]

The present study numerically investigates the oblique flow of a Walter-B type nano fluid over a convective surface. Effects of transversely applied magnetic field are also taken into account. The governing system is presented in the form of coupled differential equations by means of suitable similarity transformations which are then solved by using Spectral Quasilinearisation Method (QLM) and the Spectral Local Linearization Method (LLM). The results for velocities temperature as well as nano particle concentration are plotted against pertinent flow parameters. It is found that applied magnetic field M has opposite influence on normal and tangential components of local shear stress and it decays the local heat flux and mass flux rate at the stretching convective surface. Thermophoresis and Brownian diffusion effects on the local heat and mass flux rate are found to be non-similar in a quantitative sense. In order to signify the validity of current numerical scheme, a remarkable agreement is presented with the previous literature for some limiting cases. [ABSTRACT FROM AUTHOR]

Abstract: Heat transfer characteristics of a two-dimensional steady hydromagnetic slip flow of water based nanofluids (TiO2–water, Al2O3–water, and Cu–water) over a wedge with convective surface taking into account the effects of heat generation (or absorption) has been investigated numerically. The local similarity solutions are obtained by using very robust computer algebra software MATLAB and presented graphically as well as in a tabular form. The results show that nanofluid velocity is lower than the velocity of the base fluid and the existence of the nanofluid leads to the thinning of the hydrodynamic boundary layer. The rate of shear stress is significantly influenced by the surface convection parameter and the slip parameter. It is higher for nanofluids than the base fluid. The results also show that within the boundary layer the temperature of the nanofluid is higher than the temperature of the base fluid. The rate of heat transfer is found to increase with the increase of the surface convection and the slip parameters. Addition of nanoparticles to the base fluid induces the rate of heat transfer. The rate of heat transfer in the Cu–water nanofluid is found to be higher than the rate of heat transfer in the TiO2–water and Al2O3–water nanofluids. [Copyright &y& Elsevier]

The paper presents a numerical study to explore the possible similarity solutions as well as dual branch solutions to study the performance evaluation of various nanoparticles associated water as the base fluid in the case of steady two-dimensional forced convection boundary layer flow through a moving flat porous plate under external magnetic fields. We considered water as a base fluid embedded with the three different types of nanoparticles namely copper (Cu), alumina (Al 2 O 3) and titania (TiO 2). The governing equations are simplified by similarity approach. The resulting equations are solved numerically and the numerical results are explored through graphs and tables and discussed in detail. The influences of problem parameters are discussed for the steady solution. The paper extends results of previous works by others authors contributing to increase the scientific knowledge on the subject. The skin friction coefficient and local Nusselt number on the plane are studied as functions of the problem parameters. The study reveals that the problem considered admits of upper and lower branch solutions for moving parameter λ , magnetic parameter M , the power law parameter n , convection heat transfer b and nanoparticle volume fraction parameter ϕ. [ABSTRACT FROM AUTHOR]