ABSTRACT The pool boiling performance plays a key role in the development of high heat flux dissipating applications. The high critical heat flux and low wall superheat are two of the critical factors that affect the long-term life of devices. In this paper, enhanced pool boiling performance can be achieved by well-designed microchannels in copper surfaces using a precision diamond dicing method. The microchannel patterned surface with the channel length of 0.4 mm obtains a critical heat flux of 169.8 W/cm2, which has a 193% enhancement compared to the plain surface. Besides, the extremely low wall superheat of 3 K has been achieved, and thus the heat transfer coefficient reaches 51.8 W/cm2·K, about 738% larger than that of the plain surface. Herein, the microcavity has increased the nucleation site, the surface can promote the bubbles escape, and then the channel can continuously supply the liquid. Hence, the extremely low wall superheat at high heat flux occurs due to the rapid bubble departure and enhanced capillary feeding of liquid replenishment to active nucleation sites on the surface. The above results provide an effective way for the realization of high-performance two-phase microchannel patterned heat sinks via optimizing the microstructure geometry.

中文翻译：

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通过液体的毛细管进料提高具有极低壁过热度的微通道图案表面的池沸腾性能

摘要 池沸腾性能在高热通量消散应用的发展中起着关键作用。高临界热通量和低壁过热是影响设备长期寿命的两个关键因素。在本文中，可以通过使用精密金刚石切割方法在铜表面精心设计的微通道来提高池沸腾性能。通道长度为 0.4 mm 的微通道图案表面获得了 169.8 W/cm2 的临界热通量，与普通表面相比提高了 193%。此外，实现了3K的极低壁面过热度，传热系数达到51.8W/cm2·K，比平面大738%左右。在这里，微腔增加了形核位点，表面可以促进气泡逸出，然后通道可以连续供应液体。因此，由于气泡快速离开和液体补充到表面活性成核位置的毛细管进给增强，在高热通量下会出现极低的壁过热。上述结果为通过优化微观结构几何形状实现高性能两相微通道图案化散热器提供了有效途径。