Natural Convection in a Cylindrical and Divergent Annular Duct Fitted with Fins

摘要

The paper deals with a numerical study of natural convective heat transfer flow in a three dimensional cylindrical and divergent annular duct. The inner cylinder is subjected to a volumetric heat generation and fitted with longitudinal fins. The governing equations of mass, momentum and energy equation for both the fluid and the solid are solved by the finite volume method, using the commercially available CFD software Fluent. The effect of the inclination angle φ of the divergent and the fins number N on the profiles and contour fields of temperature and velocity as well as the average Nusselt number were investigated for φ = 0°, 15°, 23° and 45°, for a number of fins, N=1, 2 and 3. Simulations were carried out for the Rayleigh numbers Ra = 3.1.10~4 and 6.2.10~4, corresponding respectively to the volumetric heat generation, Qv = 5.10~5and 1.10~6 W/m~3. The results reveal that the increasing of the inclination angle and the fins enhance the heat transfer.