Extraordinary boiling enhancement by hybrid dividing zones of micro-nano structures

Boiling two-phase transition is considered to be the ultimate effective cooling strategy for the next generation of high-power devices in the near future in various application scenarios, such as power electronics, radar systems, and computer data centers. The liquid-solid interface plays a crucial role in the boiling phase change and the bubble evolvement. This study proposes a novel architecture of micro-nano structures using a unique hybrid dividing zone array, which can not only enhance the onset of nucleate boiling (ONB) and dramatically elevate the heat transfer coefficient (HTC), but also accelerate liquid replenishment, pushing the critical heat flux (CHF) to a much higher level. This is achieved through a superhydrophilic liquid storage zone that provides timely and continuous liquid supplementation for boiling phase change during the drying out period of the most copper surface. Compared to the plain surface copper sample, the proposed hybrid structured sample achieves about 5–7 °C earlier of ONB, up to 293% enhancement of the maximum HTC, and up to 242% improvement of CHF. Overall, this study demonstrates an effective surface enhancement approach that significantly and comprehensively improve boiling heat transfer performance, making it highly promising for cooling high-power applications. © 2024 Elsevier Ltd