Parametric study and design optimization of finned tube heat exchangers for enhanced indirect evaporative cooling

• Design guidelines for energy efficient FTHEs for HVAC. • CFD-based parametric analysis was conducted to evaluate the effects of fin geometry on performance. • Optimal fin configuration was determined, maximizing thermal effectiveness. • Correlation for Nu and Eu are developed with R 2 of 92.47% and 96.58%, respectively. This study presents a comprehensive computational analysis, parametric study and optimization of a finned-tube heat exchanger (FTHE) integrating with Multi-Directional Wind Tower (MDWT) in Indirect Evaporative Cooling (IEC) applications aimed at improving thermal performance while minimizing pressure drop ( Δ p ). A parametric investigation was conducted using validated computational fluid dynamics (CFD) simulations to assess the effects of fin height ( h f ), fin thickness ( t f ), and fin spacing ( S f ) on thermal performance and flow resistance. Key trends revealed that S f influences the heat transfer coefficient ( h ) non-linearly, while h f shows diminishing returns beyond a critical value. t f had a minor effect on Δ p but improved fin efficiency ( η f ), especially at higher Reynolds numbers ( Re ). A performance indicator was defined as the ratio of Nusselt number N u and Euler number ( E u ) to simultaneously enhance heat transfer and reduce flow resistance. A MATLAB-based optimization algorithm was then implemented to determine the configuration exhibiting the highest performance score. The optimal design was found to have a h f of 4 mm, t f of 1 mm, and S f of 2 mm, achieving a Nu of 195.57, Eu of 4.48, and Nu / E u of 43.61. The optimized geometry design observed 88.32 % increment in Nu in comparison to the base case for model validation. Correlation models are developed for Nu and Eu using log–log linearization technique and achieved high accuracy of R 2 of 92.47 % and 96.58 %, respectively. It offers reliable predictions for future design efforts. The findings provide practical insights into integrating FTHE in IEC with balanced thermal and hydraulic performance.