Bio‐Inspired Superhydrophobic Closely Packed Aligned Nanoneedle Architectures for Enhancing Condensation Heat Transfer
Bio‐Inspired Superhydrophobic Closely Packed Aligned Nanoneedle Architectures for Enhancing Condensation Heat Transfer
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DOI：
10.1002/adfm.201800634
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发表时间：
2018-06
影响因子：
19
通讯作者：
Rui Wang;Jie Zhu;Kaixin Meng;Hao Wang;T. Deng;Xuefeng Gao;Lei Jiang
中科院分区：
文献类型：
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作者：
Rui Wang;Jie Zhu;Kaixin Meng;Hao Wang;T. Deng;Xuefeng Gao;Lei Jiang
仿生冷凝液微滴自推进（CMDSP）表面由于其学术和商业价值而引起了人们的广泛兴趣。迄今为止，设计和制备具有上级冷凝传热（CHT）效率的CMDSP纳米结构仍然是一个巨大的挑战。在这里，据报道，通过原位生长和几何调节具有CMDSP功能的紧密排列的纳米针，可以将铜表面的CHT系数最大提高约320%。这些实验和理论分析表明，减小纳米针间距有助于减小冷凝液微滴的偏离直径，提高其成核密度，这两者都有利于提高CHT。相比之下，增加纳米针的尖端尺寸和高度可以分别增加液滴离开直径和膜层热阻，这两者都不利于增强CHT。显然，仅考虑超疏水效应是不够的，选择理想的纳米结构并优化其几何参数对于实现高效CHT至关重要，而这种优化可以通过简单控制纳米结构的生长时间来实现。这些发现为一级CHT界面纳米材料的设计和开发提供了新的见解。
Bionic condensate microdrop self‐propelling (CMDSP) surfaces are attracting intensive interest due to their academic and commercial values. Up to now, it is still a great challenge to design and fabricate CMDSP nanostructures with superior condensation heat transfer (CHT) efficiency. Here, it is reported that the CHT coefficient of copper surfaces can be enhanced maximally ≈320% via in situ growth and geometric regulation of closely packed aligned nanoneedles with CMDSP function. These experiments and theoretical analyses indicate that reducing the interspaces of nanoneedles can help reduce the departure diameters of condensate microdrops and increase their nucleation density, both of which are beneficial to enhance CHT. In contrast, increasing the tip size and height of nanoneedles can increase drop departure diameters and film‐layer thermal resistance, respectively, either of which is disadvantageous to enhance CHT. Clearly, only considering superhydrophobic effect is insufficient and both choosing ideal nanoarchitectures and optimizing their geometric parameters are very crucial to realize high‐efficiency CHT, which optimization can be achieved via simply controlling growth time of nanostructures. These findings offer new insights into the design and development of first‐rank CHT interface nanomaterials.