A review on the modification of circular fin and tube heat exchangers through new innovative fin shapes

Heat exchanger tubes with circular fins have been widely used in industrial and commercial applications over the past decade and are considered one of the major researcher's concerns in a range of engineering applications for their affordable cost and potential future to improve heat transfer. This review summarises the recently optimised circular fins (needle, trimmed, crimped, perforated) and how they affect heat transmission, the pressure generated and weight. Where varying fin-related parameters (fin height, fin material, the gap between fins, and number of fins) and flow-related parameters (inlet air velocity or manufacturing fin design) are aimed to optimise the performance in a different manner. In conclusion, designs of novel fin shapes remained a challenging field and demanded more studies to reinforce the existing papers to accomplish the optimum required performance.