Controlling condensation and frost growth with chemical micropatterns.
Controlling condensation and frost growth with chemical micropatterns.
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DOI：
10.1038/srep19131
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发表时间：
2016-01-22
影响因子：
4.6
通讯作者：
Collier CP
中科院分区：
文献类型：
--
作者：
Boreyko JB;Hansen RR;Murphy KR;Nath S;Retterer ST;Collier CP
在冷冻疏水表面上，面内霜生长是一种液滴间现象，在这种现象中，冷冻液滴从邻近的过冷液滴中获取水分，形成冰桥，并通过链式反应在表面上传播。到目前为止，还没有一种表面能够被动地阻止冰桥在过冷冷凝水群中的平面内增长。在这里，我们证明，如果在冷冻前用化学微模式适当地控制过冷冷凝水相邻成核位点之间的分离，液滴间的冰桥可以减缓甚至完全停止。由于相邻过冷液滴之间的边缘到边缘的分离随着生长时间的推移而减少，因此故意触发早期冻结事件以最小化新生冷凝的大小也是必要的。这些发现表明，通过设计表面来控制成核位置和时间上控制冻结事件的发生，可以被动地抑制液滴间霜的生长。
In-plane frost growth on chilled hydrophobic surfaces is an inter-droplet phenomenon, where frozen droplets harvest water from neighboring supercooled liquid droplets to grow ice bridges that propagate across the surface in a chain reaction. To date, no surface has been able to passively prevent the in-plane growth of ice bridges across the population of supercooled condensate. Here, we demonstrate that when the separation between adjacent nucleation sites for supercooled condensate is properly controlled with chemical micropatterns prior to freezing, inter-droplet ice bridging can be slowed and even halted entirely. Since the edge-to-edge separation between adjacent supercooled droplets decreases with growth time, deliberately triggering an early freezing event to minimize the size of nascent condensation was also necessary. These findings reveal that inter-droplet frost growth can be passively suppressed by designing surfaces to spatially control nucleation sites and by temporally controlling the onset of freezing events.