Dropwise condensation on superhydrophobic surfaces with two-tier roughness

Dropwise condensation can enhance heat transfer by an order of magnitude compared to film condensation. Superhydrophobicity appears ideal to promote continued dropwise condensation which requires rapid removal of condensate drops; however, such promotion has not been reported on engineered surfaces. This letter reports continuous dropwise condensation on a superhydrophobic surface with short carbon nanotubes deposited on micromachined posts, a two-tier texture mimicking lotus leaves. On such micro-/nanostructured surfaces, the condensate drops prefer the Cassie state which is thermodynamically more stable than the Wenzel state. With a hexadecanethiol coating, superhydrophobicity is retained during and after condensation and rapid drop removal is enabled. © 2007 American Institute of Physics.

Full Text

Duke Authors

Cited Authors

  • Chen, CH; Cai, Q; Tsai, C; Chen, CL; Xiong, G; Yu, Y; Ren, Z

Published Date

  • 2007

Published In

Volume / Issue

  • 90 / 17

International Standard Serial Number (ISSN)

  • 0003-6951

Digital Object Identifier (DOI)

  • 10.1063/1.2731434

Citation Source

  • SciVal