A review of the impacts of the microchannel structure on the heat transfer performance of microchannel heat exchangers

Microchannel heat exchangers have compact structure and very high heat transfer performance, making them a key technology addressing the heat dissipation challenges of high-power-density electronic devices. It has been shown that the optimization of the geometry of microchannels allows to increase the convective heat transfer coefficient during heat transfer, and to enhance the uniformity of the flow field distribution. However, the increase of the heat transfer performance often comes at the expense of high pressure drop and manufacturing costs. Performing coordinated optimization of heat transfer efficiency, flow resistance, and economic benefits has become a key challenge. Thus, this paper reviews the impacts of the microchannel geometry and surface roughness on the heat transfer performance, and explores the progress of the studies on biomimetic and composite microchannels for heat transfer enhancement. It also reviews the emerging applications of intelligent design methods to the performance prediction and multi-objective optimization, such as machine learning. Finally, it summarizes the existing studies and future development trends of high-performance microchannel heat exchangers. This paper provides a theoretical reference for the design of next-generation high-efficiency, low-resistance, and high-reliability thermal management systems.