Temperature Distribution Measurements along Helical Coiled Tube Heat Exchanger with Effect of Air Injection

Present paper try to clarify important statement that has not been addressed in the literature which is the influence of tiny air bubbles injection on temperature distribution along a vertical shell and helical coiled tube heat exchanger. Four thermocouples were installed along the shell side of the heat exchange unite in addition to the inlet and outlet thermocouples. Experiments performed with three different shell water flow rate (4, 6, and 8 1/m) and each flow rate was performed with five different air flow rate (2, 4, 6, 8, and 10 1/m) with constant air temperature 18 0C. The flow rate of the coiled tube (hot fluid) was kept constant at 2 1/m. The inlet temperature of fluid (water) in both coiled tube and shell were kept constant at 37 0C and 17 0C respectively. The obtained results showed that a mutual thermal mixing was take place once the air as tiny bubbles were injected in the shell side of the heat exchanger. Hence, a high heat transfer rate was recorded and indicated by the sudden raising of the temperature along the heat exchanger.