Topology optimization of convective heat transfer in microchannels under different working modes

Optimizing structures of microchannels is crucial for enhancing convective heat transfer. In the present study, the topology optimization (TO) method is developed to optimize the fin configuration of microchannels for cooling dies working under two different modes. Specifically, one of the dies is idle under working mode 1, while all dies are activated under working mode 2. Compared with the TO structures generated by just considering a single working mode, the TO structure generated by considering both working modes is demonstrated to exhibit remarkable adaptability to both working modes, leading to all activated dies effectively cooled. Furthermore, effects of pressure drop constraint, uniformity of heat source, and inlet position on the TO optimized structures are investigated. As the pressure drop constraint increases, the volume and quantity of the solid fins will increase and the die temperature will be reduced. TO structures designed under uniform heat sources and a modified inlet position result in worse cooling performance. Finally, all the TO structures generated are evaluated under a wide range of Reynolds numbers in terms of friction factor, Nusselt number, pumping power, and the highest temperature of dies.