scholarly journals Non-Similar Solutions for Heat and Mass Transfer from a Surface Embedded in a Porous Medium for Two Prescribed Thermal and Solutal Boundary Conditions

Author(s):  
Abdelraheem Mahmoud Aly ◽  
Ali Chamkha

This work studies the effects of homogeneous chemical reaction and thermal radiation on coupled heat and mass transfer by free convection from a surface embedded in a fluid-saturated porous medium. Two different cases of thermal and solutal boundary conditions, namely the prescribed surface temperature and concentration (PSTC) case and the prescribed heat and mass fluxes (PHMF) case are considered. The governing boundary-layer equations are formulated and transformed into a set of non-similar equations. The resulting equations are solved numerically by an accurate and efficient implicit finite-difference method. The obtained results compared with previously published work and found to be in excellent agreement. A representative set of results is displayed graphically to illustrate the influence of the radiation parameter, chemical reaction parameter and the permeability of the porous medium on the velocity, temperature and concentration fields as well as the local skin-friction coefficient, local Nusselt number and the local Sherwood number.

2007 ◽  
Vol 2007 ◽  
pp. 1-7 ◽  
Author(s):  
Mostafa A. A. Mahmoud

In the present study, an analysis is carried out to study the variable viscosity and chemical reaction effects on the flow, heat, and mass transfer characteristics in a viscous fluid over a semi-infinite vertical porous plate. The governing boundary layer equations are written into a dimensionless form by similarity transformations. The transformed coupled nonlinear ordinary differential equations are solved numerically by using the shooting method. The effects of different parameters on the dimensionless velocity, temperature, and concentration profiles are shown graphically. In addition, tabulated results for the local skin-friction coefficient, the local Nusselt number, and the local Sherwood number are presented and discussed.


2016 ◽  
Vol 2016 ◽  
pp. 1-10 ◽  
Author(s):  
Khilap Singh ◽  
Manoj Kumar

The effects of chemical reaction on heat and mass transfer flow of a micropolar fluid in a permeable channel with heat generation and thermal radiation is studied. The Rosseland approximations are used to describe the radiative heat flux in the energy equation. The model contains nonlinear coupled partial differential equations which have been transformed into ordinary differential equation by using the similarity variables. The relevant nonlinear equations have been solved by Runge-Kutta-Fehlberg fourth fifth-order method with shooting technique. The physical significance of interesting parameters on the flow and heat transfer characteristics as well as the local skin friction coefficient, wall couple stress, and the heat transfer rate are thoroughly examined.


Author(s):  
A.M. Rashad ◽  
M. Modather M. Abdou ◽  
Ali Chamkha

Magneto-hydrodynamic free convective heat and mass transfer of a viscous, incompressible, electrically conducting and chemically-reacting fluid adjacent to a vertical stretching sheet embedded in a saturated porous medium in the presence of a thermal radiation effect are investigated. The sheet is linearly stretched with uniform constant of temperature and concentration. The governing partial differential equations are transferred into a system of ordinary differential equations, which are solved numerically using a fourth order Runge-Kutta scheme with the shooting method. The effects of various parameters entering into the problem have been examined on the velocity and temperature profiles as well as the skin-friction coefficient, and Nusselt and Sherwood numbers are presented graphically and in tabular form.


2013 ◽  
Vol 10 (2) ◽  
pp. 157-168 ◽  
Author(s):  
Ali J. Chamkha ◽  
S.M.M. EL-Kabeir ◽  
A.M. Rashad

An analysis is performed to study the thermal radiation and chemical reaction effects on coupled heat and mass transfer by MHD natural convective boundary-layer flow of a micropolar fluid over a permeable truncated cone with variable surface temperature and concentration. A suitable set of dimensionless variables is used to transform the governing equations of the problem into a non-similar form. The resulting non-similar equations have the property that they reduce to various special cases previously considered in the literature. An adequate and efficient implicit, tri-diagonal 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. A representative set of numerical results for the velocity, microrotation, temperature and concentration profiles as well as the local skin-friction coefficient, local wall couple stress, local Nusselt number and the local Sherwood number is presented graphically for various parametric conditions and discussed.DOI: http://dx.doi.org/10.3329/jname.v10i2.15898


2004 ◽  
Vol 82 (6) ◽  
pp. 447-458 ◽  
Author(s):  
A A Afify

The effects of radiation and chemical reactions, in the presence of a transverse magnetic field, on free convective flow and mass transfer of an optically dense viscous, incompressible, and electrically conducting fluid past a vertical isothermal cone surface are investigated. The nonlinear boundary-layer equations with the boundary conditions are transferred by a similarity transformation into a system of nonlinear ordinary differential equations with the appropriate boundary conditions. Furthermore, the similarity equations are solved numerically by using a fourth-order Runge–Kutta scheme with the shooting method. Numerical results for the skin-friction coefficient, the local Nusselt number, the local Sherwood number are given; as well, the velocity, temperature, and concentration profiles are presented for a Prandtl number of 0.7, the chemical-reaction parameter, the order of the reaction, the radiation parameter, the Schmidt number, the magnetic parameter, and the surface temperature parameter. PACS No.: 47.70.Fw


2019 ◽  
Vol 24 (1) ◽  
pp. 53-66
Author(s):  
O.J. Fenuga ◽  
S.J. Aroloye ◽  
A.O. Popoola

Abstract This paper investigates a chemically reactive Magnetohydrodynamics fluid flow with heat and mass transfer over a permeable surface taking into consideration the buoyancy force, injection/suction, heat source/sink and thermal radiation. The governing momentum, energy and concentration balance equations are transformed into a set of ordinary differential equations by method of similarity transformation and solved numerically by Runge- Kutta method based on Shooting technique. The influence of various pertinent parameters on the velocity, temperature, concentration fields are discussed graphically. Comparison of this work with previously published works on special cases of the problem was carried out and the results are in excellent agreement. Results also show that the thermo physical parameters in the momentum boundary layer equations increase the skin friction coefficient but decrease the momentum boundary layer. Fluid suction/injection and Prandtl number increase the rate of heat transfer. The order of chemical reaction is quite significant and there is a faster rate of mass transfer when the reaction rate and Schmidt number are increased.


Sign in / Sign up

Export Citation Format

Share Document