Hydromagnetic Boundary Layer Flow Research Articles

CONVECTION HEAT AND MASS TRANSFER IN A HYDROMAGNETIC FLOW OF A MICROPOLAR FLUID OVER A POROUS MEDIUM

This study presents a mathematical analysis of a hydromagnetic boundary layer flow, heat and mass transfer characteristics on steady two- dimensional flow of a micropolar fluid over a stretching sheet embedded in a non-Darcian porous medium with uniform magnetic field in the presence of thermal radiation. The governing system of partial differential equations is first transformed into a system of non-linear ordinary differential equation using the usual similarity transformation. The resulting coupled non-linear ordinary dif- ferential equations are then solved using perturbation technique. With the help of graphs, the effects of the various important parameters entering into the prob- lem on the velocity, temperature and concentration fields within the boundary layer are separately discussed. The effects of the pertinent parameters on the

Unsteady Flow and Heat Transfer of a MHD Micropolar Fluid Over a Porous Stretching Sheet in the Presence of Thermal Radiation

AbstractA non-linear analysis has been made to study the unsteady hydromagnetic boundary layer flow and heat transfer of a micropolar fluid over a stretching sheet embedded in a porous medium. The effects of thermal radiation in the boundary layer flow over a stretching sheet have also been investigated. The system of governing partial differential equations in the boundary layer have reduced to a system of non-linear ordinary differential equations using a suitable similarity transformation. The resulting non-linear coupled ordinary differential equations are solved numerically by using an implicit finite difference scheme. The numerical results concern with the axial velocity, micro-rotation component and temperature profiles as well as local skin-friction coefficient and the rate of heat transfer at the sheet. The study reveals that the unsteady parameter S has an increasing effect on the flow and heat transfer characteristics.

Soret and Dufour Effects on Hydro Magnetic Heat and Mass Transfer over a Vertical Plate with a Convective Surface Boundary Condition and Chemical Reaction

This paper examined the hydro magnetic boundary layer flow with heat and mass transfer over a vertical plate in the presence of magnetic field with Soret and Dufour effects, chemical reaction and a convective heat exchange at the surface with the surrounding has been studied. The similarity solution is used to transform the system of partial differential equations and an efficient numerical technique is implemented to solve the reduced system by using the Runge-Kutta fourth order method with shooting technique. A comparison study with the previous results shows a very good agreement. The results are presented graphically and the conclusion is drawn that the flow field and other quantities of physical interest are significantly influenced by these parameters.

MHD Boundary Layer Flow due to Exponential Stretching Surface with Radiation and Chemical Reaction

The effects of radiation and first order homogeneous chemical reaction on hydromagnetic boundary layer flow of a viscous, steady, and incompressible fluid over an exponential stretching sheet have been investigated. The governing system of partial differential equations has been transformed into ordinary differential equations using similarity variables. The dimensionless system of differential equations was then solved numerically by the Runge-Kutta method. The skin-friction coefficient and the rate of heat and mass transfers are presented in tables whilst velocity, temperature, and concentration profiles are illustrated graphically for various varying parameter values. It was found that the rate of heat transfer at the surface decreases with increasing values of the transverse magnetic field parameter and the radiation parameter.

Heat and mass transfer of MHD convective boundary layer flow past a stretching porous wall embedded in a porous medium

The hydromagnetic convective boundary layer flow past a stretching porous wall embedded in a porous medium with heat and mass transfer in the presence of a heat source and under the influence of a uniform magnetic field is studied. Exact solutions of the basic equations of motion, heat and mass transfer are obtained after reducing them to nonlinear ordinary differential equations. The reduced equations of heat and mass transfer are solved using a confluent hypergeometric function. The effects of the flow parameters such as a suction parameter (N), magnetic parameter (M), permeability parameter (Kp), wall temperature parameter (r), wall concentration parameter (n), and heat source/sink parameter (Q) on the dynamics are discussed. It is observed that the suction parameter appears in the boundary condition ensuring the variable suction at the surface. Transverse component of the velocity increases only when magnetic field strength exceeds certain value, but the thermal boundary layer thickness and concentration distribution increase for all values. Results presented in this paper are in good agreement with the work of the previous author and also in conformity with the established theory.

Numerical Study of Chemically-Reacting Hydromagnetic Boundary Layer Flow with Soret/Dufour Effects and a Convective Surface Boundary Condition

Numerical Study of Chemically-Reacting Hydromagnetic Boundary Layer Flow with Soret/Dufour Effects and a Convective Surface Boundary Condition

MHD Flow of an Oldroyd-B Fluid Through a Porous Channel

This paper discusses the hydromagnetic boundary layer flow of an Oldroyd-B fluid in a porous channel. Both suction and injection (blowing) cases are considered. Appropriate similarity transformations are invoked to convert the partial differential equations into ordinary ones. Homotopy analysis method (HAM) is used for the presentation of analytic solution of the nonlinear differential system. Graphical results provide the salient features of the embedded flow parameters which include the Reynolds number, the Deborah numbers, and the Hartman number. Comparison between the existing numerical solution in a Maxwell fluid and present deduced series solution in a limiting sense is excellent.

Second Law Analysis for Variable Viscosity Hydromagnetic Boundary Layer Flow with Thermal Radiation and Newtonian Heating

The present paper is concerned with the analysis of inherent irreversibility in hydromagnetic boundary layer flow of variable viscosity fluid over a semi-infinite flat plate under the influence of thermal radiation and Newtonian heating. Using local similarity solution technique and shooting quadrature, the velocity and temperature profiles are obtained numerically and utilized to compute the entropy generation number. The effects of magnetic field parameter, Brinkmann number, the Prandtl number, variable viscosity parameter, radiation parameter and local Biot number on the fluid velocity profiles, temperature profiles, local skin friction and local Nusselt number are presented. The influences of the same parameters and the dimensionless group parameter on the entropy generation rate in the flow regime and Bejan number are calculated, depicted graphically and discussed quantitatively. It is observed that the peak of entropy generation rate is attained within the boundary layer region and plate surface act as a strong source of entropy generation and heat transfer irreversibility.

Hydromagnetic thermal boundary layer flow of a perfectly conducting fluid

Using successive approximation technique, an analysis of unsteady hydromagnetic boundary layer flow with thermal relaxation of perfectly conducting, viscous incompressible fluid past a semi-infinite porous plate in presence of heat absorbing sinks is carried out. The expression for velocity and temperature fields, local skin friction coefficient, local heat transfer coefficient etc have been derived when the free stream velocity exponentially depends on time. The effects of different parameters entering into the problem are shown graphically and discussed numerically.

Similarity solution of hydromagnetic heat and mass transfer over a vertical plate with a convective surface boundary condition

This paper examined the hydromagnetic boundary layer flow with heat and mass transfer over a vertical plate in the presence of magnetic field and a convective heat exchange at the surface with the surrounding has been studied. The similarity solution is used to transform the system of partial differential equations, describing the problem under consideration, into a boundary value problem of coupled ordinary differential equations and an efficient numerical technique is implemented to solve the reduced system. A comparison study with the previous results shows a very good agreement. The results are presented graphically and the conclusion is drawn that the flow field and other quantities of physical interest are significantly influenced by these parameters. Key words: Vertical plate, convective boundary condition, heat and mass transfer, magnetic field, similarity solution.

Radiation effect on mixed convection of hydromagnetic boundary layer flow of a non-Newtonian fluid at a stretching surface

Radiation effect on mixed convection of hydromagnetic boundary layer flow of a non-Newtonian fluid at a stretching surface

Unsteady MHD flow of a non-Newtonian fluid on a porous plate

This paper deals with the study of the MHD flow of non-Newtonian fluid on a porous plate. Two exact solutions for non-torsionally generated unsteady hydromagnetic flow of an electrically conducting second order incompressible fluid bounded by an infinite non-conducting porous plate subjected to a uniform suction or blowing have been analyzed. The governing partial differential equation for the flow has been established. The mathematical analysis is presented for the hydromagnetic boundary layer flow neglecting the induced magnetic field. The effect of presence of the material constants of the second order fluid on the velocity field is discussed.

Analytical solutions of hydromagnetic boundary-layer flow of a non-Newtonian power-law fluid past a continuously moving surface

The boundary-layer flow of a power-law non–Newtonian fluid over a continuously moving surface in the presence of a magnetic field B(x) applied perpendicular to the surface has been investigated. An analytical solution is obtained and compared with the numerical solution of the resulting non linear ordinary differential equation. The effects of the Stewart number (N) and the power law-index (n) on the velocity profiles and the skin-friction are studied.

Thermal radiation and buoyancy effects on hydromagnetic flow over an accelerating permeable surface with heat source or sink

Similarity equations governing steady hydromagnetic boundary-layer flow over an accelerating permeable surface in the presence of such effects as thermal radiation, thermal buoyancy, and heat generation or absorption effects are obtained. These equations are solved numerically by an implicit finite-difference method. Favorable comparisons with previously published work are obtained. The effects of the various parameters on the velocity and temperature profiles as well as the skin-friction coefficient and wall heat transfer are presented graphically and in tabulated form.

Hall effects on oscillatory MHD boundary-layer flow under variable suction

The effects of Hall current on the oscillatory hydromagnetic boundary-layer flow under variable suction, past an infinite porous flat plate in the presence of a transverse magnetic field is discussed. The expressions for velocity and skin-friction are obtained and their variations for small and large frequency of oscillations are extensively discussed.

On solutions of some unsteady flows over a continuous, moving, porous flat surface

A singular perturbation solution for hydromagnetic boundary-layer flow over a continuously moving surface with large suction is obtained and compared with its exact solution. Also, the solutions are obtained for finite and large values of t (time) and for various asymptotic cases. Flow of this type represents a new class of boundary-layer problems, with solutions substantially different from those for boundary-layer flow on a flat surface of finite length. Surprisingly, the inner solution of the problem is valid even in the outer region, and the effect of magnetic field on the flow field is almost negligible. Furthermore, it is shown that a straightforward perturbation expansion valid for all t (time) and y (space coordinate), for small suction, is not possible because of the infinite condition On y.

Hydromagnetic effects on the three-dimensional flow past a porous plate

Hydromagnetic effects on the three-dimensional flow of an electrically conducting viscous incompressible fluid past a porous plate with periodic suction has been analysed. The uniform flow is subjected to a transversely applied magnetic field. The mathematical analysis is presented for the hydromagnetic boundary layer flow neglecting the induced magnetic field. Approximate solutions for the components of velocity field and the skin-frictions due to them are obtained and discussed with the help of a graph and tables.

Hydromagnetic flow and heat transfer over a continuous, moving, porous, flat surface

Exact solutions for hydromagnetic boundary-layer flow and heat transfer over a continuous, moving, flat surface with uniform suction and internal heat generation/absorption are obtained. Flow of this type represents a new class of boundary-layer problems, with solutions substantially different from those for boundary-layer flow on a flat surface of finite length. These solutions are even exact solutions of the complete Navier-Stokes equations and the energy equation.

Unsteady hydromagnetic boundary-layer flow on a semi-infinite wall

Unsteady two-dimensional flow of a viscous, incompressible and electrically conducting fluid which is confined on one side of a semi-infinite wall, in presence of a transverse magnetic field is investigated. The wall is initially at rest and then it is suddenly accelerated in its own plane with a velocity which is an arbitrary function of the time. Solution of the problem is obtained, for two particular cases, i.e., corresponding to two free-stream velocities, with the help of the finite difference approximation technique using the explicit method for uniformly accelerated motion of the wall.

Hall effects on an oscillatory MHD flow in the Stokes problem past an infinite vertical porous plate, I

Hall effects on the hydromagnetic free convection flow of an electrically conducting incompressible viscous fluid past a steadily moving vertical porous plate has been analysed when the free stream oscillates in magnitude. The flow is subjected to a constant suction, through the porous plate, and the difference between wall temperature and the free-stream is moderately large causing the free convection currents. The mathematical analysis is presented for the hydromagnetic boundary layer flow without taking into account the induced magnetic field. This is a valid assumption for small magnetic Reynolds number. Approximate solutions for the components of velocity field and temperature field and their related quantities are obtained. The influence of various parameters entering into the problem is extensively discussed with the help of graphs and tables.