Conjugate Mixed Convection with Surface Radiation in a Vertical Channel with Symmetric and Uniform Wall Heat Generation
C. Gururaja Rao, C. Balaji and S.P. Venkateshan
The present paper provides the results of an exhaustive numerical study of the problem of two-dimensional, steady, incompressible, conjugate, laminar, mixed convection with surface radiation in a vertical parallel-plate channel with symmetric and uniform heat generation in its two walls. The fluid used is air, a radiatively transparent medium. The governing equations, written in vorticity-stream function form, are solved using a finite-volume based finite difference method. For surface radiation calculations, radiosity-irradiation method is used, while the view factors required therein are determined using the Hottel’s crossed-string method. A computer code is written for solving the above problem. A thorough investigation into fluid flow and heat transfer characteristics is made. The role of surface radiation, in influencing the various parameters, such as the wall temperature distribution, the heat transfer rate and the friction coefficient, is clearly highlighted. The effect of aspect ratio and Richardson number on all the relevant results is explored. Based on a large set of (about 250 numerical data), correlations are evolved for maximum and average wall temperatures and mean friction coefficient, for the cases of equal and unequal wall surface emissivities.