Advances in microchannel flow boiling heat transfer: mechanisms and performance optimization

Microchannel flow boiling has emerged as a promising technology for thermal management of electronic devices due to its high heat transfer coefficient, low pumping power, and compact cooling architecture. This review presents a comprehensive overview of recent advances in microchannel flow boiling heat transfer and performance optimization strategies. The fundamental mechanisms governing microchannel flow boiling are first summarized with emphasis on bubble dynamics, microscale confinement effects, interfacial phase change, and thin film evaporation. Then the effects of channel geometry, surface modification, and working fluid modification on heat transfer performance are further analyzed by elucidating how these strategies regulate the underlying mechanisms of microchannel flow boiling. Furthermore, emerging optimization strategies are discussed in terms of hybrid active passive regulation, coordinated regulation of multiple boiling mechanisms, and artificial intelligence (AI) assisted prediction and optimization. Representative approaches include topology-optimized microchannel structures, adaptive shape memory alloy (SMA)-based regulation, jet microchannel coupled cooling, and AI-assisted prediction and optimization methods. The practical limitations of existing strategies are also discussed in terms of manufacturability, durability, operational stability, cost, packaging compatibility, and system level integration. Finally, the current challenges and future research directions in microchannel flow boiling are outlined. This review provides guidance for the design and optimization of next generation thermal management systems for high power electronic and energy systems.