Heat Transfer Analysis of Melting Process over A Horizontal Three Fins Tube With Different Orientations

Abstract

In this paper, an experimental study was achieved for the melting process of a phase change material around a copper tube with three longitudinal copper fins that placed inside a rectangular plastic container as a horizontally latent thermal energy storage unit (LTESU). A paraffin wax was used as a phase change material (PCM). Some parameters were considerable in this work like the directions of fins at angles of (0°, 30°, 60° and 90°), temperature of the water entering to the finned tube at (55, 65 and 75) °C and the effect of water flow rate inside the finned tube at (7.5, 15 and 22.5) liters / min. The law of energy conservation was used to find the amount of potential energy stored inside paraffin wax by calculating the energy liberated from the hot water entering the system. The results showed that the effect of the temperature of water entering to the system has given increases in the melting with rate of (64.3)% at a temperature of (75) °C compared to the water temperature at (55) ° C. Also the increases in melting rate has reached to (17.5)% at the flow rate (22.5) liters / min compared to the flow rate (7.5) liters / min . The melting has reached to (25.6)% at the angle of (30) degrees compared to the angle of (90) degrees. The results also showed that when using temperature of (55) ° C, water flow rate (7.5) l/min and rotation angle of (30°) that the maximum enhancement ratio in the melting fraction reached to (5.74)% and when using the water temperature (65) degrees and flow rate (15) l/min and the angle of rotation (30°) the maximum enhancement ratio was (11.9)%. When using the incoming water temperature (75) °C and flow rate (22.5) l/min and the angle of rotation at (30°) the maximum enhancement ratio was (12.03)%. The highest percentage of time savings was also reached (12.03%) at the angle of (30°) compared with (90°). Finally, the highest percentage of energy liberated was reached at a water temperature (75) ° C and fin rotation angle (30°) and the flow rate (22.5) l / min was reached (5355) watts.