Mixed Convective Heat Transfer Flow Research Articles

A Theoretical Study of Steady MHD mixed convection heat transfer flow for a horizontal circular cylinder embedded in a micropolar Casson fluid with thermal radiation

In this study, an investigation is carried out for laminar steady mixed 2D magnetohydrodynamic (MHD) flow of micropolar Casson fluid with thermal radiation over a horizontal circular cylinder with constant surface temperature. In the present study, an investigation is carried out on the effects of physical parameters on Casson fluid non dimensional numbers. The governing nonlinear partial differential equations and the controlling boundary conditions are derived for this case study. Furthermore, these equations are solved numerically using finite difference technique known as Keller Box Method (KBM). The effects of non-dimensional governing parameters, namely Casson parameter, mixed convection parameter, magnetic parameter, radiation parameter on the Nusselt number and local friction coefficient, as well as temperature, velocity and angular velocity are discussed and shown graphically. It is noticed that the local skin friction and the local Nasselt number has decrement behaviors when increasing the values the Casson parameter. But the opposite happens when the mixed convection parameter λ increase. It is found that the results in this study are in good agreement with previous studies. This proves that calculations using KBM method and the chosen step size are accurate enough for this type of problems.

Mixed convection in micropolar nanofluid flow through entrapped triangular enclosures and linear stability analysis considering magnetic effects and heat generation and absorption

In the present investigation, numerical computation for mixed convection heat transfer flow within entrapped triangular enclosures saturated with a micropolar nanofluid and linear stability analysi...

Mixed Convective Magnetohydrodynamic Heat Transfer Flow of Williamson Fluid Over a Porous Wedge

The present article examines the influence of thermal radiation on two-dimensional incompressible magnetohydrodynamic (MHD) mixed convective heat transfer flow of Williamson fluid flowing past a porous wedge. An adequate similarity transformation is adopted to reduce the fundamental boundary layer partial differential equations of Williamson fluid model in to a set of non-linear ordinary differential equations. The solutions of the resulting nonlinear system are obtained numerically using the fifth order numerical scheme the Runge-Kutta-Fehlberg method. The effects of different pertinent physical parameter such as magnetic parameter, Williamson parameter, radiation parameter and Prandtl number on temperature and velocity distributions are observed through graph.

Buoyancy and metallic particle effects on an unsteady water-based fluid flow along a vertically rotating cone

This article is devoted to analyzing the effects of different types of nanoparticles, namely, copper (Cu), aluminum ( Al2O3 and titanium (TiO2), within the base fluid (water) on an unsteady mixed convection heat transfer flow over a rotating cone. This model concerns a nanofluid which incorporates only the nanoparticle volume fraction for each mentioned particle. The governing equations are solved numerically with the help of the Runge-Kutta-Fehlberg method. The influences of significant parameters, like the volume fraction of three types of nanoparticles with water as a base fluid, are reported and discussed through graphs of velocities, temperature, skin friction coefficient and reduced Nusselt number. The results are recovered for the existing literature when the contribution of nanoparticles is negligible. In conclusion it is observed that, for both assisting and opposing flow, the local Nusselt number increases with an increase of the nanoparticle volume fraction and the TiO2-water has a higher Nusselt number when it is compared to both Al2O3 and Cu-water.

Entropy generation in turbulent mixed convection heat transfer to highly variable property pipe flow of supercritical fluids

In this study, a two dimensional CFD code has been developed to investigate entropy generation in turbulent mixed convection heat transfer flow of supercritical fluids. Since the fluid properties vary significantly under supercritical conditions, the changes of entropy generation are large. The contribution of each of the mechanisms of entropy production (heat transfer and energy dissipation) is compared in different regions of the flow. The results show that the mechanisms of entropy generation act differently in the near wall region within the viscous sub-layer and in the region away from the wall. The effects of the wall heat flux on the entropy generation are also investigated.

Mixed Convective Heat Transfer Flow of Nanofluid past a Permeable Vertical Flat Plate with Magnetic Effects: A Finite Element Study

Steady, two dimensional mixed convection laminar boundary layer flow of incompressible nanofluid along a permeable vertical semi-infinite flat plate with magnetic field effects has been investigated numerically. The resulting govering equations (obtained from the boussinesq) with associated boundary conditions are solved, using a robust, extensively validated, Galerkin Finite Element Method for different types of spherical shaped metal oxide nanoparticles with two different ratios of the nanolayer thickness to the original particle radius (0.02 or 0.1). The effects of the parameters governing the problems are discussed and shown graphically. The present study is of immediate interest in next-generation solar film collectors, heat exchangers technology, material processing exploiting vertical surfaces and all those processes which are highly affected with heat transfer.

MHD mixed convective heat transfer flow about an inclined plate

Mixed convection heat transfer about a semi-infinite inclined plate in the presence of magneto and thermal radiation effects is studied. The fluid is assumed to be incompressible and dense. The nonlinear coupled parabolic partial differential equations governing the flow are transformed into the non-similar boundary layer equations, which are then solved numerically using the Keller box method. The effects of the mixed convection parameter Ri, the angle of inclination α, the magnetic parameter M and the radiation–conduction parameter Rd on the velocity and temperature profiles as well as on the local skin friction and local heat transfer parameters. For some specific values of the governing parameters, the results are compared with those available in the literature and a fairly good agreement is obtained.

FLOW PATTERNS OF MIXED CONVECTION IN A HORIZONTAL SQUARE CHANNEL FLOW

An experimental study of mixed-convection heat transfer flow of a CuSO4 + H2SO4 + H2O solution in a horizontal channel was performed. Unstable temperature gradients imposed by a heated bottom initiated an ascending (secondary) flow of light boundary layer fluid into the free stream. The shadowgraph technique was used to visualize the flow and to determine the nature and effect of thermally driven secondary flows in a horizontal channel with heated top and bottom surfaces and insulated side walls. The ranges of the parameters studied in the present work for the square channel are Pr = 5–7, Re = 100–1,000, and Grqb = 2·8 × 106−2·5 × 107. Flow visualization revealed Ike existence of four regimes corresponding to laminar forced convection, laminar mixed convection, transitional mixed convection, and turbulent free convection. Also, the onset of secondary flow was found to be delayed by decreasing the Grash of number and / or by increasing the Reynolds number. A direction for future study of mixed thermosoluta...