Biphilic Nanoporous Surfaces Enabled Exceptional Drag Reduction and Capillary Evaporation Enhancement

Author(s)

Xianming Dai, University of South CarolinaFollow
Fanghao Yang, University of South CarolinaFollow
Ronggui Yang
Xinyu Huang, University of South Carolina - ColumbiaFollow
William A. Rigdon
Xiaodong Li
Chen Li

Document Type

Article

Subject Area(s)

Mechanical Engineering, Physics

Abstract

Simultaneously achieving drag reduction and capillary evaporation enhancement is highly desired but challenging because of the trade-off between two distinct hydrophobic and hydrophilic wettabilities. Here, we report a strategy to synthesize nanoscale biphilic surfaces to endow exceptional drag reduction through creating a unique slip boundary condition and fast capillary wetting by inducing nanoscopic hydrophilic areas. The biphilic nanoporous surfaces are synthesized by decorating hydrophilic functional groups on hydrophobic pristine multiwalled carbon nanotubes. We demonstrate that the carbon nanotube-enabled biphilic nanoporous surfaces lead to a 63.1% reduction of the friction coefficient, a 61.7% wetting speed improvement, and up to 158.6% enhancement of capillary evaporation heat transfer coefficient. A peak evaporation heat transfer coefficient of 21.2W/(cm2 K) is achieved on the biphilic surfaces in a vertical direction.

Publication Info

Published in Applied Physics Letters, Volume 105, Issue 19, 2014, pages 191611-1-191611-5.

Rights

© Applied Physics Letters, 2014, American Institute of Physics

Dai, X., Yang, F., Yang, R., Huang, X., Rigdon, W., Li, X., Li, C. (2014). Biphilic Nanoporous Surfaces Enabled Exceptional Drag Reduction and Capillary Evaporation Enhancement. Applied Physics Letters, 105(19), 191611-1-191611-5.

http://dx.doi.org/10.1063/1.4901962