Multi-objective optimization of manifold microchannel heat sink with corrugated bottom impacted by nanofluid jet

The manifold microchannel heat sink (MMCHS) has been widely used for heat dissipation of high heat -flux electronic devices. To reduce the thermal resistance and flow resistance of MMCHS and obtain bet-ter heat dissipation performance, a novel manifold microchannel heat sink with corrugated bottom (CB-MMCHS) is proposed in this study. The flow and heat transfer characteristics of nanofluid jet impinge-ment on CB-MMCHS are numerically studied under different structural parameters and nanofluid concen-trations, respectively. The results show that the channel width ratio gamma has the most significant effect on total thermal resistance Rt and pumping power Pp of CB-MMCHS among structural parameters, increasing nanofluid concentrations can enhance the heat transfer but also increases pumping power consumption. In order to obtain the optimal structural design, multi-objective optimization is performed with the ob-jective of minimizing Rt and Pp. It is found that the optimized CB-MMCHS has lower thermal resistance and flow resistance compared with MMCHS. When Rt of optimized CB-MMCHS is 0.2794 K/W, Pp de-creases to 0.1674 W, 43.81% lower than MMCHS; When Pp is 0.2979 W, Rt decreases to 0.2367 K/W, 14.86% lower than MMCHS. In addition, the compromise solution with minimum Rt is selected by intro-ducing TOPSIS combined with entropy weight method.(c) 2022 Elsevier Ltd. All rights reserved.