Heat Transfer Enhancement by Perforated and Louvred Fin Heat Exchangers

Altwieb, Miftah, Mishra, Rakesh, Aliyu, Aliyu M. , Kubiak, Krzysztof J., , and , (2022) Heat Transfer Enhancement by Perforated and Louvred Fin Heat Exchangers. Energies, 15 (2). p. 400. ISSN 1996-1073

Full content URL: https://doi.org/10.3390/en15020400

Heat Transfer Enhancement by Perforated and Louvred Fin Heat Exchangers
Published Open Access manuscript
energies-15-00400-v2.pdf - Whole Document
Available under License Creative Commons Attribution 4.0 International.

Item Type:Article
Item Status:Live Archive


Multi-tube multi-fin heat exchangers are extensively used in various industries. In the current work, detailed experimental investigations were carried out to establish the flow/heat transfer characteristics in three distinct heat exchanger geometries. A novel perforated plain fin design was developed, and its performance was evaluated against standard plain and louvred fins designs. Experimental setups were designed, and the tests were carefully carried out which enabled quantification of the heat transfer and pressure drop characteristics. In the experiments the average velocity of air was varied in the range of 0.7 m/s to 4 m/s corresponding to Reynolds numbers of 600 to 2650. The water side flow rates in the tubes were kept at 0.12, 0.18, 0.24, 0.3, and 0.36 m3/h corresponding to Reynolds numbers between 6000 and 30,000. It was found that the louvred fins produced the highest heat transfer rate due to the availability of higher surface area, but it also produced the highest pressure drops. Conversely, while the new perforated design produced a slightly higher pressure drop than the plain fin design, it gave a higher value of heat transfer rate than the plain fin especially at the lower liquid flow rates. Specifically, the louvred fin gave consistently high pressure drops, up to 3 to 4 times more than the plain and perforated models at 4 m/s air flow, however, the heat transfer enhancement was only about 11% and 13% over the perforated and plain fin models, respectively. The mean heat transfer rate and pressure drops were used to calculate the Colburn and Fanning friction factors. Two novel semiempirical relationships were derived for the heat exchanger’s Fanning and Colburn factors as functions of the non-dimensional fin surface area and the Reynolds number. It was demonstrated that the Colburn and Fanning factors were predicted by the new correlations to within ±15% of the experiments.

Keywords:Heat exchangers, louvred fins, heat transfer effectiveness, Fanning friction factor, Colburn factor
Subjects:H Engineering > H141 Fluid Mechanics
H Engineering > H300 Mechanical Engineering
Divisions:College of Science > School of Engineering
ID Code:48015
Deposited On:04 Jul 2022 11:41

Repository Staff Only: item control page