Flexible conformable hydrophobized surfaces for turbulent flow drag reduction.
Flexible conformable hydrophobized surfaces for turbulent flow drag reduction.
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DOI：
10.1038/srep10267
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发表时间：
2015-05-15
影响因子：
4.6
通讯作者：
Newton MI
中科院分区：
文献类型：
--
作者：
Brennan JC;Geraldi NR;Morris RH;Fairhurst DJ;McHale G;Newton MI
近年来，大量的工作集中在使用超疏水表面进行减阻应用。当超疏水表面以 Cassie-Baxter 状态浸入水下且水与表面粗糙特征的顶部接触时，会保留一个称为腹甲的气体层。在这种状态下，腹甲允许在表面上发生滑动，从而减少阻力。在这项工作中，我们报告了使用两种不同方法生产的柔性且相对大面积的超疏水表面：通过在铜网上电沉积创建大粗糙度特征；通过将碳纳米粒子（烟灰）嵌入聚二甲基硅氧烷（PDMS）中，形成了小粗糙度特征。两种样品均被制成直径小于12毫米的圆柱体。为了表征样品，拍摄了扫描电子显微镜 (SEM) 图像和共焦显微镜图像。将每个样品浸入水中拍摄共焦显微镜图像，以显示腹甲的范围。与润湿状态相比，疏水化电沉积铜网圆柱体的阻力降低高达 32%。与普通气缸相比，超疏水状态下的碳烟覆盖气缸的阻力降低了 30%。这些结果是针对雷诺数为 10,000 至 32,500 的湍流而获得的。
In recent years extensive work has been focused onto using superhydrophobic surfaces for drag reduction applications. Superhydrophobic surfaces retain a gas layer, called a plastron, when submerged underwater in the Cassie-Baxter state with water in contact with the tops of surface roughness features. In this state the plastron allows slip to occur across the surface which results in a drag reduction. In this work we report flexible and relatively large area superhydrophobic surfaces produced using two different methods: Large roughness features were created by electrodeposition on copper meshes; Small roughness features were created by embedding carbon nanoparticles (soot) into Polydimethylsiloxane (PDMS). Both samples were made into cylinders with a diameter under 12 mm. To characterize the samples, scanning electron microscope (SEM) images and confocal microscope images were taken. The confocal microscope images were taken with each sample submerged in water to show the extent of the plastron. The hydrophobized electrodeposited copper mesh cylinders showed drag reductions of up to 32% when comparing the superhydrophobic state with a wetted out state. The soot covered cylinders achieved a 30% drag reduction when comparing the superhydrophobic state to a plain cylinder. These results were obtained for turbulent flows with Reynolds numbers 10,000 to 32,500.
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影响因子：
4
作者：
McHale, G.;Shirtcliffe, N. J.;Newton, M. I.
通讯作者：
Newton, M. I.
影响因子：
3.6
作者：
Daniello, Robert;Muralidhar, Pranesh;Rothstein, Jonathan P.
通讯作者：
Rothstein, Jonathan P.
影响因子：
4.6
作者：
Fukagata, K;Kasagi, N;Koumoutsakos, P
通讯作者：
Koumoutsakos, P
图案化疏水表面滑移长度的形状依赖性
影响因子：
4
作者：
Gu, Xiaokun;Chen, Min
通讯作者：
Chen, Min
DOI：
10.1016/s0142-727x(03)00061-4
发表时间：
2003-08-01
影响因子：
2.6
作者：
Catalano, P;Wang, M;Moin, P
通讯作者：
Moin, P