A low power consumption fractal microchannel heat sink based on hierarchical ribs

Thermal management is a crucial factor in electronic devices with increasing power density due to the miniaturization, high power, and high performance of these devices. To meet the dual requirements of high heat flux and low power consumption, a heat sink based on a fractal microchannel with hierarchical ribs structure and multiple outlets is proposed in this work. The rib structure increases the heat dissipation performance of the heat sink by enlarging the heat transfer area and disturbing flow. However, the addition of the rib structure also narrows the microchannel, which increases the pressure drop. To further reduce the pressure drop, the hierarchical rib structure is optimized, and multiple outlets are added. The optimization of the hierarchical rib structure reduces the pressure drop by 30% without compromising the heat dissipation performance. The addition of multiple outlets reduces the power consumption, with simulation results showing that the pressure drop of four outlets is just a quarter of one outlet. Moreover, the heat uniformity is improved by the optimization. Finally, the thermal performance of one selected heat sink tested by experiment is matched the simulation results. This study provides a potential method for high heat flux with low power consumption heat dissipation. The proposed heat sink structure with hierarchical rib structures and multiple outlets has promising potential for use in electronic devices with high power density, where efficient thermal management is critical.