Numerical modeling and algorithm-enhanced design of multi-segment microchannels for thermal management in power electronics

AbstractMicrofluidic cooling plays a critical role in managing the escalating heat flux in high-power-density integrated devices. However, conventional designs based on simple parallel or uniform channels face significant limitations in simultaneously reducing thermal resistance and pressure drop. This study proposes a systematic multistage microchannel design and optimization strategy. Four types of microchannel structures, including parallel straight, two-stage, complementary two-stage, and three-stage channels, were designed and evaluated through Computational Fluid Dynamics (CFD) simulations and experiments. The complementary two-stage microchannel achieved the best balance between thermal resistance and pressure drop, reducing thermal resistance to 0.802 K/W while maintaining a temperature increase of no more than 2 °C. Furthermore, an optimization algorithm based on SurrogateOpt solver was applied to refine sectional channel widths for embedded and manifold microchannel structures. The optimized embedded microchannel achieved a 31.4% reduction in thermal resistance and supported a heat flux density of up to 1500 W/cm2. In the manifold microchannel structure, the optimized thermal resistance was reduced to 1.095 K/W, effectively balancing thermal and hydraulic performance. These findings demonstrate the effectiveness of multistage channel system design and algorithmic optimization for enhancing thermal management in high-performance integrated cooling systems.