THERMAL SCIENCE

International Scientific Journal

NUMERICAL SIMULATION AND OPTIMIZATION OF HYPERBOLIC DIMPLED LOUVERED FIN HEAT EXCHANGER

ABSTRACT
Louvered fin heat exchangers are widely used in automotive air conditioning systems owing to their compact structure and excellent heat transfer performance. To further improve their thermal-hydraulic performance, this study proposes a novel hyperbolic dimpled louvered fin. Numerical simulations were performed to compare the flow and heat transfer characteristics of the hyperbolic dimpled louvered fin with those of the conventional louvered fin over a Reynolds number range of 100-500. In addition, the structural parameters were optimized using response surface methodology. The results show that the dimpled structure enhances local flow disturbance, induces vortex formation, and improves convective heat transfer. The optimal parameter combination was determined as an aspect ratio of k = 4.3, a louver angle of θ = 29.4°, and a fin pitch of Lp = 2.08 mm. Among these parameters, the louver angle had the greatest influence on the comprehensive performance factor, and a significant interaction was observed between the louver angle and the aspect ratio. Under the optimized conditions, the hyperbolic dimpled louvered fin exhibited better overall performance than the conventional louvered fin. Compared with the conventional louvered fin, the heat transfer factor j increased by 2.3%-4.4%, the friction factor f increased by 2.5%-3.1%, and the comprehensive performance factor JF increased by 2.1%-3.5%. These results indicate that the proposed fin structure can enhance heat transfer while causing only a limited increase in flow resistance, providing useful guidance for the design of high-performance louvered fin heat exchangers.
KEYWORDS
PAPER SUBMITTED: 2026-03-15
PAPER REVISED: 2026-07-01
PAPER ACCEPTED: 2026-07-11
PUBLISHED ONLINE: 2026-09-03
DOI REFERENCE: https://doi.org/10.2298/TSCI260315163C
[1] Li J., Su J., et al., Research on the Performance of Radiators in Hybrid Vehicle Thermal Management Systems, World Electric Vehicle Journal, 16(2025), pp. 89
[2] Sahoo, R. R., Effect of various shape and nanoparticle concentration based ternary hybrid nanofluid coolant on the thermal performance for automotive radiator, Heat and Mass Transfer, 57(2021), 5, pp. 1-15
[3] Bhaiyat, T. I., Schekman, S., et al., Off-design performance of a louvered fin-tube heater core in an automotive climate control system. Applied Thermal Engineering, 161(2019), 114155
[4] Zhou, Q., Liu, S., et al., Novel method for assessment of thermal performance of louvered fin and flat tube heat exchangers, Acta Mechanica Sinica, 41(2025), 6, pp. 1-11
[5] Altwieb, M., Mishra, R., et al., Heat transfer enhancement by perforated and louvred fin heat exchangers, Energies, 15(2022), 2, pp. 400
[6] Ma, Y., Hou, Q., et al., Performance study on a printed circuit heat exchanger composed of novel airfoil fins for supercritical CO2 cycle cooling system, Thermal Science, 27(2023), 1B, pp. 891-903
[7] Okbaz, A., Pınarbaşı, A., et al., Experimental investigation of effect of different tube row-numbers, fin pitches and operating conditions on thermal and hydraulic performances of louvered and wavy finned heat exchangers, International Journal of Thermal Sciences, 151(2020), 106256
[8] Wanglertpanich, K., Kittichaikarn, C., Heat transfer efficiency enhancement using zigzag louvered fin, Numerical Heat Transfer, 79(2020), 4, pp. 278-293
[9] Zou, Z., Zhu, Z., et al., Experimental investigation on the thermal-hydraulic performance of serrated fins and novel serrated-perforated fins for PFHEs in cryogenic helium systems, Energy, 330(2025), 136845
[10] Lei, Y., Li, Y., et al., Design and performance analysis of the novel shell-and-tube heat exchangers with louver baffles, Applied Thermal Engineering, 125(2017), 870-879
[11] Zhang, X., Huang, Y., et al., Numerical Investigation of the Air-Side Performance of Louver Fin-and-Tube Radiators Having Rectangular, Tapered and Airfoil Section Configuration, Energy Reports, 8(2022), pp. 11799-11809
[12] Ferrero, M., Scattina, A., et al., Louver Finned Heat Exchangers for Automotive Sector: Numerical Simulations of Heat Transfer and Flow Resistance Coping With Industrial Constraints, Journal of Heat Transfer, 135(2013), 12, 121801
[13] Kong, Y. Q., Yang, L. J., et al., Effects of continuous and alternant rectangular slots on thermo-flow performances of plain finned tube bundles in in-line and staggered configurations, International Journal of Heat and Mass Transfer, 93(2016), pp. 97-107
[14] Saleem, A., Kim, M. H., Airside Thermal Performance of Louvered Fin Flat-Tube Heat Exchangers with Different Redirection Louvers, Energies, 15(2022), 16, pp. 5904
[15] Nair, G. S., Oumer, A. N., et al., Flow and Heat Transfer Simulation Analysis of 3D Compact Heat Exchanger, Journal of Advanced Research in Fluid Mechanics and Thermal Sciences, 88(2021), 3, pp. 71-87
[16] Nakhchi, M. E., Esfahani, J. A., et al., Numerical study of turbulent flow inside heat exchangers using perforated louvered strip inserts, International Journal of Heat and Mass Transfer, 148(2020), 119143
[17] Yang, F., Zhou, G., et al., Optimization of a micro-channel structure of an elliptical louver fin, Thermal Science, 23(2019), 4, pp. 2429-2436
[18] Chang, Y., Hsu, K., et al., A generalized friction correlation for louver fin geometry, International Journal of Heat and Mass Transfer, 43(2000), 12, pp. 2237-2243
[19] Chang, Y., Wang, C., A generalized heat transfer correlation for louver fin geometry, International Journal of Heat and Mass Transfer, 40(1997), 3, pp. 533-544
[20] Okbaz, A., Pınarbaşı, A., et al., An experimental, computational and flow visualization study on the air-side thermal and hydraulic performance of louvered fin and round tube heat exchangers, International Journal of Heat and Mass Transfer, 121(2018), pp. 153-169
[21] Jinglong, Z., Xingjun, H., et al., Effects of Rectangular Wing Vortex Generators on the Thermal-Hydraulic Performance of Louvered Fin and Flat Tube Heat Exchanger, Journal of Thermal Science, 32(2023), 2, pp. 628-642
[22] Zarri, A., Botana, M. B., et al., Aerodynamic investigation of the turbulent flow past a louvered-fin-and-tube automotive heat exchanger, Experimental Thermal and Fluid Science, 155(2024), 111182

© 2026 Society of Thermal Engineers of Serbia. Published by the Vinča Institute of Nuclear Sciences, National Institute of the Republic of Serbia, Belgrade, Serbia. This article is an open access article distributed under the terms and conditions of the Creative Commons Attribution 4.0 International licence