Multi-objective topology optimization of a liquid-cooled microchannel for high power positive thermal coefficient heater with irregular design domain

High power density electronic devices require compact and efficient cooling systems. In this paper, a multi-objective topology optimization method is employed to design the liquid-cooled channel for a high power positive thermal coefficient heater with an irregular design domain. The optimization seeks to simultaneously minimize power consumption and maximize total heat generation. The accuracy of the numerical analysis is validated by comparing the experimental results of the serpentine channel with pin fins. The maximum relative errors in average temperature and pressure drop are 6.9 % and 18.6 %, respectively. The simulated temperature contours of the heating resistance closely match the experimental results. Compared with 4 conventional designs, the optimized design shows best overall performance in hydraulic and thermal performance. The results demonstrate that the topology optimized channel exhibits the best temperature uniformity and achieves the lowest average temperature, more than 10 °C lower than other designs. Furthermore, the topological channel exhibits a low pressure drop comparable to that of parallel channels. Moreover, the effects of the Reynolds number, fluid volume fraction and weighting factors on the topology results are investigated. The results indicate increasing the Reynolds number or the fluid volume fraction will expand the cooling channel area and generate more small branches, thereby enhancing thermal performance. For the specific case in this study, the weighting factors of the thermal and hydraulic objectives have slight impact on the topology results.