Invention Journal of Research Technology in Engineering & Management (IJRTEM) ISSN: 2455-3689 www.ijrtem.com Volume 1 Issue 6 ǁ August. 2016 ǁ PP 07-21
Effect of Thermal Radiation and Radiation Absorption On Unsteady Convective Heat And Mass Transfer Flow In A Vertical Channel With Travelling Thermal Waves C Sulochana1, Ramesh H2,Tayappa H3.
(1Dept. of mathematics, Gubarga University, Kalaburgi. India.) (2Govt. P U College Chikkanargunda, Gadag. India.) 3 ( Asst. Professor, SSA Govt. First Grade College Bellary. India.)
Abstract: In this paper, we discuss the combined influence of thermal radiation, chemical reaction and radiation absorption on free connective heat and mass transfer flow of a viscous electrically conducting fluid in a non-uniformly heated vertical channel .The walls are maintained at non-uniform temperature and a uniform concentration is maintained on the walls. The coupled equations governing the flow, heat and mass transfer have been solved by using a perturbation technique with the slope of the boundary temperature as a perturbation parameter. The expression for the velocity, the temperature, concentration, the rate of heat and mass transfer are derived and are analysed for different variations of the governing parameters G,R,M,, Sc,Q1,, 1, N, N1,k, P and x.
Key words: Heat and Mass transfer, Radiation Absorption, Thermal Radiation and Travelling Thermal waves. I. INTRODUCTION Transport of momentum and thermal energy in fluid – saturated porous media with low porosities with commonly described by Darcy’s model for conservation of momentum and by an energy equation based on the velocity field found from this model Kaviany [13]. In contrast to rocks, soil, sand and other media that do fall in this category, usually have high porosity, Vajravelu [31] examined the steady flow of heat transfer in a porous medium with high porosity. Raptis [23] studies mathematically the case of time varying two-dimensional natural convective heat transfer of an incompressible electrically conducting, viscous fluid through a high porous medium bounded by an infinite vertical porous plate. Jaiswal and Soundalgekhar [11] studied the natural convection in a porous medium with high porosity. A phenomenological theory of combined heat and mass transfer in porous media was previously established by Devries [6, 7] and Philip and Devries [20] commonly known as Devries mechanism model, its practical usefulness is widely recognized in describing the simultaneous heat and mass transfer with in a wide range of porous media. Experimental studies for mixed convection heat and mass transfer in the horizontal channel has been studied by Kamotani et al [9] and Maughan and Incorporal [16]. The heat and mass transfer through porous medium has been carried out by several authors [1, 2, 18, 26, 28, 30] under different conditions. In the above mentioned investigations the boundary walls are maintained at constant temperature. However, there are a few physical situations which warrant the boundary temperature to be maintained non-uniform. It is evident that in forced or free convection flow in a channel (pipe) a secondary flow can be created either by corrugating the boundaries or by maintaining non-uniform wall temperature. Such a secondary flow can be of interest in a few technological processes. For example, in drawing optic glass fibers of extremely low loss and band width the processes of modified chemical vapour deposition (MCVD) [14, 27] has been suggested in recent times. Performs from which these fibers are drawn are made by passing a gaseous mixture into a fused-silica tube which is heated locally, by an oxy-hydrogen flame particulate of So2Geo2 composition are formed from the mixture and collect on the interior of the tube. Subsequently these are fined to form a vitreous deposit as the flame traversed along the tube. The deposition is carried out in the radial direction through the secondary flow created due to non–uniform wall temperature. The application of electromagnetic fields in controlling the heat transfer as in aerodynamic heating leads to the study of magneto hydrodynamics heat transfer. The MHD heat transfer has gained significance owing to advancement of space technology. The MHD heat transfer can be divided into sections. One contains problems in which the heating is an incidental by product of the electromagnetic fields as in the MHD generators and pumps etc. and the second contains of problems in which the primary use of electromagnetic fields is to control the heat transfer [30]. With the fuel crisis
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