Header microstructure effects on hotspot cooling in microchannel heat sinks

Among the microstructural parameters influencing hotspot cooling in microchannel heat sinks, the header design plays a particularly significant role in thermal management. This study conducted numerical simulations to investigate hotspot heat dissipation in pin-fin microchannel heat sinks with inlet and outlet header structures. A detailed analysis was performed on the temperature distribution, flow characteristic, and field synergy in pin-fin microchannel heat sinks with different header microstructures. Furthermore, the mechanisms by which these microstructures influence heat transfer in the hotspot region were investigated. The results indicate that, under varying header parameters, changes in the field synergy angle within the microchannels are consistent with variations in the convective heat transfer coefficient. Moreover, the header configuration with Mhead = 2 mm and Hhead = 0.55 mm yielded the lowest maximum temperature on the hotspot surface, reducing it by 6 K compared to the peak temperature observed among all cases. This study offers a new approach to mitigating the heat dissipation challenges associated with local hotspot.