Effect of Variable Viscosity, Dufour, Soret and Thermal Conductivity on Free Convective Heat and Mass Transfer of Non-Darcian Flow past Porous Flat Surface

Isaac L Animasaun,Anselm O Oyem

doi:10.4236/ajcm.2014.44030

Abstract

The motion of incompressible fluid of a variable fluid viscosity and variable thermal conductivity with thermal radiation, Dufour, Soret with heat and mass transfer over a linearly moving porous vertical semi-infinite plate with suction is investigated. The governing equations are transformed into a system of coupled nonlinear ordinary differential equations using similarity transformations with dimensionless variables and solved numerically using shooting method with Runge-Kutta fourth-order method and Newton-Raphson’s interpolation scheme implemented in MATLAB. The result showed that with increase in Dufour and Soret parameter, fluid velocity increases and temperature increases with increase in variation of Dufour while, temperature decreases with increase in Soret. The effects of variable fluid viscosity, variable thermal conductivity, thermal radiation, Soret, Dufour, Prandtl and Schmidt parameters on the dimensionless velocity, temperature and concentration profiles are shown graphically.

Highlights

Fluid flow problems of free convective, heat and mass transfer through a porous medium had been given atten-How to cite this paper: Animasaun, I.L. and Oyem, A.O. (2014) Effect of Variable Viscosity, Dufour, Soret and Thermal Conductivity on Free Convective Heat and Mass Transfer of Non-Darcian Flow past Porous Flat Surface
Oyem tion due to its applications in many engineering problems such as nuclear reactor design, geothermal systems, petroleum engineering applications, evaporation at the surface of a water body, control of pollutants in ground water, energy transfer in a wet cooling tower, food processing cooler [1] [2], and the problem of heat and mass transfer flow of a laminar boundary layer over a stretching sheet in a saturated porous medium has an important application in the metallurgy and chemical engineering fields
Layek et al [3] considered the effects of thermal radiation and variable fluid viscosity on free convective flow and heat transfer past a porous stretching surface while, Alharbi et al [4] investigated the heat and mass transfer of MHD viscoelastic fluid flow through a porous medium over a stretching sheet with chemical reactions, due to the importance of Soret (Thermal-diffusion) and Dufour (Diffusion-thermo) effects on the fluids with very light molecular weight as well as medium molecular weight

Summary

Introduction

Fluid flow problems of free convective, heat and mass transfer through a porous medium had been given atten-. (2014) Effect of Variable Viscosity, Dufour, Soret and Thermal Conductivity on Free Convective Heat and Mass Transfer of Non-Darcian Flow past Porous Flat Surface. Et al [14] investigated the effects of variable properties on MHD heat and mass transfer flow near a stagnation point towards a stretching sheet in a porous medium with thermal radiation and adopted the model of Prasad, et al [15] for temperature dependent viscosity and thermal conductivity and incorporated the stagnation point velocity into their momentum equation. We want to study the effects of variable fluid viscosity, variable thermal conductivity, Dufour and Soret on free convective heat and mass transfer of non-Darcian flow past a porous flat surface taking into account radiation effects using Rosseland approximation in modeling the radiative heat transfer

Mathematical Formulation

Numerical Solution

Results and Discussion

Conclusion