Transient Hybrid Cooling of Dual Heat Sources in a Diverging–Converging Channel

This study presents an original numerical investigation of transient forced‐convection heat transfer in a channel coupled with a phase change material (PCM) for advanced thermal management of electronic components. The proposed configuration integrates a flow‐guiding obstacle together with porous and solid fins, aiming to intensify convective heat transfer and enhance heat removal efficiency. A comprehensive parametric analysis is conducted to assess the effects of key hydrodynamic and geometric parameters, including the heated block geometry (rectangle, triangle, square, semi‐circle), Reynolds number , axial obstacle displacement , channel height , obstacle size , and cavity inclination angle . The results demonstrate that forced convection intensification, primarily governed by the Reynolds number, leads to a maximum temperature reduction of up to 6.3%. The height of the enlarged channel section significantly influences the thermal performance, with a reduction in this height leading to an approximately 9% decrease in temperature. The effect of the flow‐guiding obstacle size is also investigated, showing that an increase in its size leads to a reduction in the maximum temperature of up to 8% for Re = 600. Moreover, an optimal cavity inclination of provides additional improvement in heat transfer efficiency. These findings highlight a robust and high‐performance design strategy for thermal management in electronic cooling applications.