EFFECT OF PERFORATED AND SMOOTH FINS ON THERMAL PERFORMANCE OF A LATENT HEAT ENERGY SYSTEM

Abstract

This work includes design, manufacture and improvement of a Waste Heat Recovery System (WHRS) for thermal energy storage unit by using PCM technique. Paraffin wax produced by Al-Durra refinery (major Iraqi oil company) has been used as a phase change material for this purpose. The heat transfer enhancement has been investigated experimentally and numerically by using perforated and smooth copper strips which inserted within paraffin wax in the form of fins. These coppers fins were welded with copper pipes in which water is flow inside it during the discharge process. The effect of fins and perforated fins with three different size of diameters (2,3 and 4 mm), on the heat transfer of PCM during melting process has been investigated to selecting the optimum among them. The results obtained indicate that inserting copper strips mainly rises heat transfer by conduction inside PCM and decreases the time of melting by about, 16% due to high thermal conductivity of this strips and the smooth fins are more useful than perforated fins for improving the thermal properties of paraffin wax and the rate of heat transfer. It is also found that the increase in the diameter of the perforations led to decrease the thermal performance of the fins.