Thermal Management of Electronic Components in a Ventilated Cavity: A Comparative Study of Phase Change Material, Air, and Hybrid Finned Heat Sink Configurations Under Mixed Convection and Surface Radiation

ABSTRACT This study presents a comparative numerical investigation of thermal management in a rectangular cavity subjected to mixed convection and surface radiation. The system consists of two horizontally aligned electronic components, each equipped with a finned heat sink attached to its upper surface. Three heat sink designs are considered: (a) fins fully filled with phase change material (PCM), (b) conventional fins filled with air, and (c) an alternating arrangement of PCM and air between fin layers. A parametric analysis is conducted to evaluate the effects of the Reynolds number and the inlet flow inclination angle on the thermal performance of the system. The results indicate that increasing the Reynolds number enhances convective heat transfer, with maximum temperature reductions of approximately 0.43% (Case 1), 4.1% (Case 2), and 0.49% (Case 3). Decreasing the flow inclination angle from 60° to 0° further improves cooling performance, yielding reductions of 0.15% (Case 1), 1.06% (Case 2), and 0.21% (Case 3). A comparative assessment reveals that the PCM‐integrated configuration (Case 1) provides the best overall thermal performance, achieving a reduction in the maximum block temperature of up to 32 K compared to the air‐filled configuration (Case 2), obtained at Re = 200 and θ = 60°.