How a raindrop gets shattered on biological surfaces
How a raindrop gets shattered on biological surfaces
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DOI：
10.1073/pnas.2002924117
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发表时间：
2020-06-23
影响因子：
11.1
通讯作者：
Jung, Sunghwan
中科院分区：
文献类型：
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作者：
Kim, Seungho;Wu, Zixuan;Jung, Sunghwan
动植物的许多生物表面(如鸟类的羽毛、昆虫的翅膀、植物的叶子等)是超疏水的，具有不同长度尺度的粗糙表面。以前的研究主要集中在生物表面上低速撞击时的一种简单的跌落反弹行为。然而，我们观察到，高速撞击的液滴表现出更复杂的动力学行为，具有意想不到的类似冲击波的模式：在扩散液滴上形成数百个类似冲击波的波，然后液滴突然破碎，并伴随着多个成核孔。这种液滴动力学导致扩散液滴的快速回缩，从而使接触时间减少了两倍以上。我们的结果可能有助于揭示通过波诱导的液滴碎裂降低吸热动物的体温过低风险和促进真菌孢子传播的潜在生物学优势。
Many biological surfaces of animals and plants (e.g., bird feathers, insect wings, plant leaves, etc.) are superhydrophobic with rough surfaces at different length scales. Previous studies have focused on a simple drop -bouncing behavior on biological surfaces with low -speed impacts. However, we observed that an impacting drop at high speeds exhibits more complicated dynamics with unexpected shock -like patterns: Hundreds of shock -like waves are formed on the spreading drop, and the drop is then abruptly fragmented along with multiple nucleating holes. Such drop dynamics result in the rapid retraction of the spreading drop and thereby a more than twofold decrease in contact time. Our results may shed light on potential biological advantages of hypother- mia risk reduction for endothermic animals and spore spreading enhancement for fungi via wave -induced drop fragmentation.