Numerical investigation of natural convection for vertical flat plate with fins

Abstract

Paper presented at the 9th International Conference on Heat Transfer, Fluid Mechanics and Thermodynamics, Malta, 16-18 July, 2012.

A finite-volume-based computational study of steady laminar natural convection from a finned isothermal vertical plate with different fin arrays has been carried out to determine the heat transfer augmentation factor with different fin aspect ratio, fin spacing and inclination of fin. Heat transfer behaviors with the fins have been analyzed by examining variations of the local and average Nusselt numbers in two- dimensional flow. Four different fin arrays heights (H = 6, 12, 18, 24 mm) and four different angles of inclination ( θ = 45°, 60°,75°, 90°) are considered. In order to understand the heat transfer characteristics of this problem, a total of 96 cases for each of conductive and non- conductive fins are considered. It is found that significant heat transfer augmentation is obtained for conductive (20% higher augmentation factor when the fin aspect ratio is 6, and angle of inclination is 60° and pitch-to-length ratio is 0.2) and non-conductive fins (10% higher augmentation factor, at fin aspect ratio of 8, angle of inclination at 45° and pitch-to- length ratio at 0.5). A general correlation has been developed to predict the average Nusselt number for fin arrays as a function of different fin configurations.