Abstract Emerging issues in boiling heat transfer include enhancing heat transfer uniformity/stability, and critical heat flux (CHF). Microcavity structures improve heat transfer uniformity/stability by departing bubbles with arranged formation due to pinning effects and regular pitch. Ultrasonic actuation induces an acoustic field on departed bubbles, and this enhances contact line instability between the bubble and microcavity structures, resulting in an increased dissipation rate of smaller bubbles. In this study, we demonstrate that synergetic effects from microcavity structures and ultrasonic actuation can enhance CHF and thermal stability while also improving temporal/spatial temperature uniformity. Applying microcavity structures with ultrasonic actuation, we observe smaller and faster bubbles' departure with the proposed formation. These bubble departure characteristics on the microcavity surface with ultrasonic actuation enhance CHF and thermal stability by delaying bubble coalescence and ensuring liquid paths between smaller and faster-departed bubbles. Thus, when ultrasonic actuation is applied to the microcavity structure, CHF increased by 20%, and temporal/spatial temperature variations near CHF were reduced to less than 1/2 and 1/3, respectively, compared to no actuation case. This research will help to understand the interaction of ultrasonic wave and bubbles, and to show the way to overcome CHF limitations of passive methods using microsized structures.

中文翻译：

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通过超声波驱动增强微结构表面上的沸腾传热

摘要 沸腾传热中的新问题包括提高传热均匀性/稳定性和临界热通量 (CHF)。由于钉扎效应和规则间距，微腔结构通过以排列的形式离开气泡来提高传热均匀性/稳定性。超声波驱动在离开的气泡上产生声场，这增强了气泡和微腔结构之间的接触线不稳定性，导致较小气泡的耗散率增加。在这项研究中，我们证明了微腔结构和超声波驱动的协同效应可以增强 CHF 和热稳定性，同时还可以改善时间/空间温度均匀性。应用超声驱动的微腔结构，我们观察到更小和更快的气泡随着提议的形成而离开。在超声波驱动的微腔表面上的这些气泡离开特性通过延迟气泡聚结并确保较小和快速离开的气泡之间的液体路径来增强 CHF 和热稳定性。因此，当超声驱动应用于微腔结构时，与没有驱动的情况相比，CHF 增加了 20%，并且 CHF 附近的时间/空间温度变化分别减少到小于 1/2 和 1/3。这项研究将有助于了解超声波和气泡的相互作用，并展示克服使用微型结构的被动方法的 CHF 局限性的方法。