UNSTEADY MAGNETOHYDRODYNAMICS HEAT AND MASS TRANSFER THROUGH POROUS MEDIA

Sulemana, M. 258 PAGES (45236 WORDS) Mathematics Thesis

Unsteady heat and mass transfers are important transport phenomena that are found in many engineering and industrial applications. In such systems, the variations in the fluid flow result in variations in the heat flux for fluid-solid temperature difference. In this study, analytical and theoretical investigations of some non-linear problems arising from unsteady heat and mass transfer through porous media are considered. Analytical models are developed. These are non-linear mathematical models for unsteady boundary layer flow past a vertical plate in the presence of heat source and transverse magnetic field embedded in a porous medium; non-linear mathematical models for unsteady hydromagnetic convective heat and mass transfer past an impulsively started infinite vertical surface with Newtonian heating in porous medium; and non-linear mathematical models for unsteady hydromagnetic boundary layer flow over an exponentially stretching flat surface in a porous chemically reactive medium. These mathematical models are developed to measure the effects of unsteadiness and other physiochemical parameters (such as radiation effects, mass diffusion, buoyancy forces, Lorentz force, velocity ratio, momentum diffusion, porous medium, chemical species, etc.) in the flow in order to understand heat and mass flow in porous media and to be able to predict related processes. These models are solved in exact form employing Laplace Transform Techniques. One major observation is that the magnetic field parameter is effective in reducing flow. The study concluded that all the controlling parameters have effects on the flow and can be used to control the flow kinematics in practice.