Transient Thermal Management of Heat‐Generating Blocks in a Partitioned Rectangular Cavity Using Forced Convection, Phase Change Material, Guiding Obstacle, and Fins

ABSTRACT This study numerically examines transient heat transfer in a rectangular cavity integrating forced convection and latent heat storage. Three heat‐generating blocks are mounted on a conductive plate separating an upper air region from a lower PCM domain. Heat is removed by forced airflow and conducted toward the PCM, whose thermal storage capacity is enhanced by vertical fins attached to the plate. The transient governing equations are solved using the finite element method. A parametric study evaluates the influence of fin shape and number , Reynolds number , obstacle position and inclination (), cavity inclination angle (), block thermal conductivity , and PCM melting temperature (). The results indicate that rectangular fins improve thermal performance, lowering the maximum block temperature by up to 13.67 K compared with triangular fins. Increasing the Reynolds number from 100 to 400 reduces peak temperatures by approximately 4.6%–5.0%. An optimal cavity inclination angle of is identified. In addition, a guiding obstacle at the optimal position effectively directs airflow, reducing the maximum temperature by 4.14%, a moderate fin number (), high block thermal conductivity , and a PCM with a higher melting temperature ( K) significantly enhance cooling efficiency. While increasing the Reynolds number strengthens the average Nusselt number, optimal obstacle configuration maximizes convective heat transfer, whereas larger channel heights tend to weaken it. Overall, the combined action of forced convection, fin‐assisted conduction, and latent heat storage emerges as an efficient approach for thermal management of electronic devices.