Department of Mechanical Engineering, University of South Carolina, Columbia, SC, 29208, USA.
Department of Mechanical Engineering, City University of Hong Kong, Hong Kong, China.
Adv Mater. 2020 Jan;32(2):e1905117. doi: 10.1002/adma.201905117. Epub 2019 Nov 11.
Development of smaller, faster, and more powerful electronic devices requires effective cooling strategies to efficiently remove ever-greater heat. Phase-change heat transfer such as boiling and evaporation has been widely exploited in various water-energy industries owing to its efficient heat transfer mode. Despite extensive progress, it remains challenging to achieve the physical limit of flow boiling due to highly transitional and chaotic nature of multiphase flows as well as unfavorable boundary layer structures. Herein, a new strategy that promises to approach the physical limit of flow boiling heat transfer is reported. The flow boiling device with multiple channels is characterized with the design of micropinfin fences, which fundamentally transforms the boundary layer structures and imparts significantly higher heat transfer coefficient even at high heat flux conditions, in which boiling heat transfer is usually deteriorated due to the development of dryout starting from outlet regions and severe two-phase flow instabilities. Moreover, the approaching of physical limit is achieved without elevating pressure drop.
开发更小、更快、更强的电子设备需要有效的冷却策略，以有效地排出越来越大的热量。由于其高效的传热模式，相变传热（如沸腾和蒸发）已在各种水-能源工业中得到广泛应用。尽管取得了广泛的进展，但由于多相流的高度过渡和混沌性质以及不利的边界层结构，仍然难以达到流动沸腾的物理极限。在这里，报告了一种有望接近流动沸腾传热物理极限的新策略。具有多个通道的流动沸腾装置的特点是微针肋的设计，它从根本上改变了边界层结构，并赋予了更高的传热系数，即使在高热通量条件下也是如此，因为沸腾传热通常会因从出口区域开始的干涸和严重的两相流不稳定性而恶化。此外，在不提高压降的情况下实现了接近物理极限。
