Numerical Investigation of the Effect of Fin Thickness and Number on the Performance Enhancement of Air-Cooled Heat Exchangers

Subject Areas : Journal of New Applied and Computational Findings in Mechanical Systems

Ehsan Hosseinzadeh ¹ , علی فلاوند جوزایی ^{2 *}

1 - Department of Mechanical Engineering, Ahv.C. , Islamic Azad University, Ahvaz, Iran.
2 -

Received: 2025-07-13 Accepted : 2025-08-17 Published : 2025-08-26

Keywords: Air cooler, fin, heat transfer, pressure drop, performance evaluation criteria (PEC).,

Abstract :

Air coolers are essential equipment in the oil, gas, and petrochemical industries. In this study, the effects of fin type (circular, rectangular, and hexagonal), fin thickness, and fins per inch (FPI) on the thermal and hydraulic performance of air coolers were analyzed using Aspen B-JAC and EES software. The results showed that increasing FPI from 3 to 12 significantly enhances heat transfer rate (about 49.6% for circular fins and 51.5% for hexagonal fins), while pressure drop in this range increases only slightly (around 1%). The highest performance coefficient (PEC) of the heat exchanger was observed for all fin types at an FPI of 12. Additionally, with increasing fin thickness and FPI, both heat transfer rate and pressure drop increase, but the increase in heat transfer is more pronounced between 0.2 mm and 0.4 mm fin thickness, whereas pressure drop increases more sharply beyond this range. Finally, increasing fin thickness results in a decrease in the cooler’s performance coefficient, with a smaller reduction between 0.2 mm and 0.4 mm thickness and a steeper decline thereafter.

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