Thermal‐Hydraulic Performance Analysis of Laminar and Turbulent Flow in Finned Heat Transfer Systems

ABSTRACT This study presents a comprehensive computational analysis comparing the thermal–hydraulic performance of laminar and turbulent flow in finned heat transfer systems under identical geometrical and boundary conditions. Using ANSYS Fluent, three‐dimensional CFD simulations were performed with the SST k – turbulence model for turbulent flow and a standard laminar model for low‐Reynolds‐number conditions. The selected finned geometry is representative of passive cooling heat sinks and compact heat exchangers used in electronics cooling, battery thermal management, and energy systems. The primary objectives were to evaluate and compare velocity, temperature, pressure, Reynolds number, and skin friction coefficient distributions in both flow regimes, and to identify optimal fin design parameters for enhanced heat transfer. Key findings show that for laminar flow, velocity ranged from 0 to 0.129 m/s, static temperature from 305 to 320 K, static pressure from −0.02 to 0.064 Pa, Reynolds number from 128 to 243, and skin friction coefficient from 0.0048 to 0.01. For turbulent flow, velocity extended up to 0.235 m/s, static temperature from 300 to 320 K, static pressure from −0.02 to 0.064 Pa, Reynolds number from 2658 to 3736, and skin friction coefficient from 0.00487 to 0.012. Streamline patterns were visualized to elucidate flow development and heat transfer mechanisms. The results demonstrate that turbulent flow significantly enhances heat transfer due to intensified mixing, whereas laminar flow exhibits lower pressure drops. This work provides a systematic, CFD‐based comparison that bridges a gap in the literature and offers practical guidelines for the design of efficient finned heat exchangers in both flow regimes.