STUDY OF HEAT-TRANSFER IN A HORIZONTAL CYLINDER WITH FINS

The purpose of this paper is to investigate, numerically, the effect o f internal fins on the flaw pattern, temperature distribution and heat transfer between concentric horizontal cylinders. A Galerkin finite e lement method is adopted for the discretization of the governing equat ions. The numerical procedure consists in solving series of transient problems of increasing Ra. Results are presented using air (Pr = 0.7) with Rayleigh numbers ranging from 10(3) to 10(6) for different fin co nfigurations (1 and 2), geometries (sharp, round and divergent tip) an d lengths (I = 0.25, 0.5 and 0.75). They are illustrated in terms of i sotherms, Velocity fields, Nusselt numbers and fin efficiencies. Confi guration 2 presents a heat transfer rate 10% above that of configurati on 1, at Ra = 10(6) The heat transfer is about the same for the three geometries, but the best fin efficiency is associated with the fin wit h a round tip.