Thermo-hydraulic Performance Assessment of a Compact Heat Exchanger by Varying Plate Fins

Abstract

Compact heat exchangers are the devices that allow having larger surface area density which is provided by the enlargement of the fins. Frequently plate fins are chosen to achieve this and several forms of this fin types are used in several applications such as rectangular plain fin, offset strip fin, wavy fin, louvered and perforated fins. In this particular work, the effect of the fins on the performance of a compact heat exchanger is studied. In order to determine distinguishing features of the fins, 2D models of a plain fin, louvered fin and offset strip fin with 3 and 4 offsets are calculated numerically by a commercially available CFD software. In the study, 6 offset strip and 3 louver and 3 plain fin cases are run for five different air velocities and the results are summarized for the heat transfer coefficient, pressure drop, Colburn j and friction factors with regard to the changing velocities. The results are summarized for varying fin pitches which allows to determine the impact of it on the performance of the heat exchangers.