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A numerical investigation on the impacts of heater length increased from left corner along with the bottom wall in a Cu-water nanofluid-filled porous cavity in the existence of MHD and thermal radiation is performed out. The bottom wall is heated with two different types of heater (both uniform and nonuniform) separately. Three various lengths of heater are considered. Constant cold upper horizontal wall moves in the positive direction. The other sidewalls and excluding the heating portion of the bottom wall are considered to be adiabatic. The system of dimensionless form of governing equations is solved by finite volume method (FVM) with appropriate boundary and initial conditions and SIMPLE algorithm has been employed for the pressure term. For both types of heating, the highest heat transfer is attained with the length of heater L H = 1 / 4 for all taken Richardson number. The effect of magnetic field is very low on heat transfer with the thermal source length L H = 1 / 2 and nonuniform heating in free convection regime. On increasing the heater length in nonuniform heating, overall heat transfer rate is decreased first and then raised. The percentage of increasing of average Nusselt number with an increase of thermal radiation parameter in nonuniform heating is higher than uniform heating. The effect of magnetic field is significant for all taken solid volume fraction in uniform heating than the nonuniform heating with heater length L H = 1 / 2. [ABSTRACT FROM AUTHOR]

The MHD phase change heat transfer of a phase change substance in the presence of a uniform magnetic field is theoretically studied in a cavity. A fixed grid method associated with the enthalpy–porosity method is utilized. The governing equations are transformed into a non-dimensional form and solved using the finite element method. The impacts of the crucial parameters such as the Hartmann number and the inclination angle on the phase change process are investigated. It is found that any increase in Hartmann number and the inclination angle of the cavity leads to a decrease in the rate of the melting process. [ABSTRACT FROM PUBLISHER]

In this work, the effect of a variable spatial magnetic field on ferro-nanofluid flow and heat transfer in a double-sided lid-driven enclosure with a sinusoidal hot wall is investigated. The working fluid is a mixture of iron oxide (Fe3O4) nanoparticles and water and is referred to as a ferro-nanofluid. The control volume-based finite element method (CVFEM) is used to solve the governing equations in the stream function–vorticity formulation. In deriving the governing equations for this investigation, the effect of both ferro-hydrodynamics and magneto-hydrodynamics is taken into account. The numerical calculations are performed for different governing parameters namely; the Reynolds number, nanoparticle volume fraction, magnetic number (arising from Ferrohydrodynamics (FHD) consideration), and the Hartmann number (arising from Magnetohydrodynamics (MHD) consideration). The results show that an enhancement in heat transfer has a direct relationship with the Reynolds number and the Hartmann number, but it has an inverse relationship with the magnetic number. Also, it can be concluded that the Nusselt number increases with the increase of the nanoparticle volume fraction, magnetic number, and the Reynolds number while the opposite trend is observed for the Hartmann number. [ABSTRACT FROM AUTHOR]

The problem of unsteady, laminar, combined forced-free convection flow in a square cavity in the presence of internal heat generation or absorption and a magnetic field is formulated. Both the top and bottom horizontal walls of the cavity are insulated while the left and right vertical walls are kept at constant and different temperatures. The left vertical wall is moving in its own plane at a constant speed while all other walls are fixed. A uniform magnetic field is applied in the horizontal direction normal to the moving wall. A temperature-dependent heat source or sink is assumed to exist within the cavity. The governing equations and conditions are solved numerically by the finite-volume approach along with the alternating direct implicit (ADI) procedure. Two cases of thermal boundary conditions corresponding to aiding and opposing flows are considered. Comparisons with previously published work are performed and the results are found to be in excellent agreement. A parametric study is conducted and a set of representative graphical results is presented and discussed to illustrate the influence of the physical parameters on the solution. [ABSTRACT FROM AUTHOR]

This work is focused on steady, laminar, coupled heat and mass transfer by natural convective boundary layer flow over a permeable isothermal truncated cone in the presence of magnetic field and radiation effects. A suitable set of dimensionless variables is used and nonsimilar equations governing the problem are obtained. The resulting equations have the property that they reduce to various special cases previously considered in the literature. An adequate implicit, tridiagonal finite difference scheme is employed for the numerical solution of the obtained equations. Various comparisons with previously published work are performed and the results are found to be in excellent agreement. Representative results for the velocity, temperature, and concentration profiles as well as the local skin-friction coefficient; local Nusselt number and the local Sherwood number illustrating the influence of the Hartmann number; the concentration to thermal buoyancy ratio; and the wall mass transfer coefficient are presented and discussed. [ABSTRACT FROM AUTHOR]

Analyzes the mixed convection flow along a vertical permeable plate in a porous medium of a transverse magnetic field. Derivation of continuum boundary layer equations; Process of wall heat transfer; Detection of non-uniform fluid mass transfer in the plate surface.