N.B.V.Rama deva prasad, Assistant professor in Mathematics, Sri Balaji P.G.College, Anantapur, Dr.P.Raveendra Nath, Assistant professor, Department of Mathematics, Sri Krishnadevaraya
University College of Engineering and Technology, S.K. University, Anantapur - 515 003,.
Abstract We discuss the free and forced convection flow through a porous medium in a coaxial cylindrical duct where the boundaries are maintained at constant temperature and concentration. The effect of density variation is confined to the buoyancy term under Boussinesq approximation. The momentum, energy and diffusion equations are coupled equations. In order to obtain a better insight into this complex problem, we make use of Galerkin finite element analysis with quadratic polynomial approximations. The behaviour of velocity, temperature and concentration is analysed at different axial positions. Key words: Heat Transfer, Mass Transfer,Porous medium,Radiation effect
1.Introduction. Transport phenomena involving the combined influence of thermal and concentration buoyancy are often encountered in many engineering systems and natural environments. There are many applications of such transport processes in the industry, notably in chemical distilleries, heat exchangers, solar energy collectors and thermal protection systems. Convection flows through horizontal porous channel whose inner surface is maintained at constant temperature while the other surface is maintained at circumferentially varying sinusoidal temperature[4 and 6].The flow is generated by periodical traveling waves imposed on the outer cylinder and the inner cylinder is maintained at constant temperature. Chen and Yuh  have investigated the heat and mass transfer characteristics of natural convection flow along a vertical cylinder under the combined buoyancy effects of thermal and species diffusion.Antonio...