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In this paper a modification of existing mathematical model of MHD radiative incompressible fluid-flow over exponentially stretching sheet is given by accumulating equation of mass transfer under an influence of chemical reaction. Using local non-similarity variables method, governing equations for heat and mass transfer of viscous fluid-flow are efficiently remodeled into the system of dimensionless PDE, and later on the obtained system of dimensionless PDE is tackled numerically using MATLAB built in solver bvp4c. Graphs of temperature, velocity and concentration profiles are explained through variation of different values of physical parameters. Significant effects of several parameters, for example radiation and magnetic parameters, Eckert and Prandtl numbers on local skin-friction coefficient, local Nusselt and Sherwood numbers are computed in tabular form. [ABSTRACT FROM AUTHOR]

In this paper, the theoretical study on the laminar boundary-layer flow of ferrofluid with influences of magnetic field and thermal radiation is investigated. The viscosity of ferrofluid flow over a solid sphere surface is examined theoretically for magnetite volume fraction by using boundary-layer equations. The governing equations are derived by applied the non-similarity transformation then solved numerically by utilizing the Keller-box method. It is found that the increments in ferroparticles (Fe3O4) volume fraction declines the fluid velocity but elevates the fluid temperature at a sphere surface. Consequently, the results showed viscosity is enhanced with the increase of the ferroparticles volume fraction and acts as a pivotal role in the distribution of velocity, temperature, reduced skin friction coefficient, and reduced Nusselt number of ferrofluid. [ABSTRACT FROM AUTHOR]

The present analysis discusses the effects of thermal-diffusion with thermal radiation, Joule heating and internal heat generation on peristaltic flow of a non-Newtonian fluid obeying Jeffery model. Heat and mass transfer are also taken into consideration, the flow is between two co-axial tubes under the effect of radially varying magnetic field. The inner tube is uniform and at rest, while the outer tube is flexible with sinusoidal wave traveling. The problem is modulated mathematically by a system of partial differential equations which describes the equations of momentum, heat, and mass transfer. These equations are solved analytically under the assumptions of long wave length and low-Reynolds number in non-dimensional form. The solutions are obtained as a functions of physical parameters of the problem. The radially varying magnetic field effect on the temperature and concentration distributions is analyzed and it is shown that the increase of Hartman number tends to reduce the temperature, while it increases the concentration. [ABSTRACT FROM AUTHOR]

Cooling period of liquid metal while flowing under imposed magnetic and electrical field was studied for laminar steady flow condition. Computational analyses were done by ANSYS Fluent software MHD module. For applied each constant value of magnetic field induction (B = 0 T, B = 0.05 T, B = 1 T), the electrical field intensity was applied positively as E+ (1e-4, 1e-5) V/m and negatively as E-(-1e-4, -1e-5) V/m. Increase of the E+ field intensity decreased the local temperature (increased cooling rate) but also increased the heat flux and Nusselt number. Also, decrease of E- in the opposite direction increased the temperature but also decreased the heat flux and Nusselt number. It could be signified that by the application of magnetic field or together with electrical field, the heat transfer could be improved or attenuated. [ABSTRACT FROM AUTHOR]

In this study, heat and mass transfer characteristic of unsteady nanofluid flow between parallel plates is investigated. The important effect of Brownian motion and thermophoresis has been included in the model of nanofluid. The governing equations are solved via differential transformation method. The validity of this method was verified by comparison previous work which is done for viscous fluid. The analytical investigation is carried out for different governing parameters namely: the squeeze number, Hartmann number, Schmidt number, Brownian motion parameter, thermophoretic parameter, and Eckert number. The results indicate that skin friction coefficient has direct relationship with Hartmann number and squeeze number. Also it can be found that Nusselt number increases with increase of Hartmann number, Eckert number, and Schmidt number but it is decreases with augment of squeeze number. [ABSTRACT FROM AUTHOR]

In the present study, numerical simulation of magnetohydrodynamic mixed convection heat transfer and fluid flow has been analyzed in a lid-driven enclosure provided with a constant flux heater. Governing equations were solved via differential quadrature method. Moving wall of the enclosure has constant temperature and speed. The calculations were performed for different Richardson number ranging from 0.1 to 10, constant heat flux heater length from 0.2 to 0.8, location of heater center from 0.1 to 0.9, Hartmann number from 0 to 100 and aspect ratio from 0.5 to 2. Two different magnetic field directions were tested as vertical and horizontal. It was found that results of differential quadrature method show good agreement with the results of literature. The magnetic field was more effective when it applied horizontally than that of vertical way. In both direction of magnetic field, it reduced the flow strength and heat transfer. Thus, it can be used as an important control parameter for heat and fluid flow. [ABSTRACT FROM AUTHOR]

This paper deals with the problem of thermal radiation effects on magnetohydro-dynamic flow and heat transfer in a channel with porous walls of different permeability. The equations governing the flow are coupled non-linear partial differential equations. By introducing the stream function, the governing partial differential equations are reduced to ordinary differential equations. The governing equations which are coupled and highly non-linear are first linearized by quasi-linearization technique and obtained numerical solution by using implicit finite difference scheme. The effects of various parameters, namely, Reynolds number, permeability parameter, Hartmann number, Prandtl number, and thermal radiation parameter, entering into the problem on the velocity field and temperature distribution are shown graphically. [ABSTRACT FROM AUTHOR]

Motivated by increasingly being used magnetohydrodynamic micropumps for pumping biological and chemical specimens, this study presents a simplified magnetohydrodynamic flow model based upon steady-state, incompressible and fully developed laminar flow theory in rectangular channel to offer the characteristics of magnetohydrodynamic pumps for prediction of pumping performance in magnetohydrodynamic flow. The non-linear governing equations of motion and energy including viscous and Joule dissipation are solved numerically for velocity and temperature distributions. To aim this goal a finite difference approximation based code is developed and utilized. In addition, the effects of magnetic flux density, applied electric current and channel size on flow velocity field as well as thermal behavior are investigated in various working medium with different physical properties. The entropy generation rate is discussed also. The simulation results are in good agreement with experimental data from literature. [ABSTRACT FROM AUTHOR]

An investigation of unsteady magnetohydrodynamic free convective flow and mass transfer during the motion of a viscous incompressible fluid through a porous medium, bounded by an infinite vertical porous surface, in a rotating system is presented. The porous plane surface and the porous medium are assumed to rotate in a solid body rotation. The vertical surface is subjected to uniform constant suction perpendicular to it and the temperature at this surface fluctuates in time about a non-zero constant mean. Analytical expressions for the velocity, temperature and concentration fields are obtained using the perturbation technique. The effects of rotation parameter, permeability parameter, Hartmann number, and frequency parameter on the flow characteristics are discussed. It is observed that the primary velocity component decreases with the increase in either of the rotation parameter, the permeability parameter, or the Hartmann number. It is also noted that the primary skin friction increases whenever there is an increase in the Grash of number or the modified Grash of number. It is clear that the heat transfer coefficient in terms of the Nusselt number decreases in the case of both air and water when there is an increase in the Hartmann number. It is observed that the magnitude of the secondary velocity profiles increases whenever there is an increase in either of the Grash of number or the modified Grash of number for mass transfer or the permeability of the porous media. Concentration profiles decreases with an increase in the Schmidt number. [ABSTRACT FROM AUTHOR]