Drag reduction in Stokes flows over spheres with nanostructured superhydrophilic surfaces

被引：37

作者：

Byon, Chan ^{[1
,2
]}

Nam, Youngsuk ^{[1
]}

Kim, Sung Jin ^{[2
]}

Ju, Y. Sungtaek ^{[1
]}

机构：

[1] Univ Calif Los Angeles, Los Angeles, CA 90095 USA

[2] Korean Adv Inst Technol, Taejon, South Korea

来源：

JOURNAL OF APPLIED PHYSICS | 2010年 / 107卷 / 06期

关键词：

drag reduction; flow simulation; hydrophilicity; laminar flow; nanofluidics; VELOCITY;

D O I：

10.1063/1.3353842

中图分类号：

O59 [应用物理学];

学科分类号：

070305 [高分子化学与物理];

摘要：

Nanostructured surfaces offer opportunities to modify flow induced drag on solid objects. Measurements of the terminal velocity reveal that the drag associated with laminar Stokes flows can be reduced for spheres with nanostructured superhydrophilic as well as superhydrophobic surfaces. Numerical simulations suggest that the formation of recirculating or nearly stagnant flow zones leads to significant reduction in the friction drag. Such reduction, however, is offset by an increase in the form drag that arises from nonuniform pressure distributions. Our work motivates further studies to optimally balance the friction and form drag and control resistance to laminar flows over objects with nanostructured surfaces.

引用

页数：3

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