Dropwise condensation of low surface tension fluids on omniphobic surfaces

Konrad Rykaczewski, Adam T. Paxson, Matthew Staymates, Marlon L. Walker, Xiaoda Sun, Sushant Anand, Siddarth Srinivasan, Gareth H. McKinley, Jeff Chinn, John Henry J Scott, Kripa K. Varanasi

Research output: Contribution to journalArticle

112 Scopus citations

Abstract

Compared to the significant body of work devoted to surface engineering for promoting dropwise condensation heat transfer of steam, much less attention has been dedicated to fluids with lower interfacial tension. A vast array of low-surface tension fluids such as hydrocarbons, cryogens, and fluorinated refrigerants are used in a number of industrial applications, and the development of passive means for increasing their condensation heat transfer coefficients has potential for significant efficiency enhancements. Here we investigate condensation behavior of a variety of liquids with surface tensions in the range of 12 to 28 mN/m on three types of omniphobic surfaces: smooth oleophobic, re-entrant superomniphobic, and lubricant-impregnated surfaces. We demonstrate that although smooth oleophobic and lubricant-impregnated surfaces can promote dropwise condensation of the majority of these fluids, re-entrant omniphobic surfaces became flooded and reverted to filmwise condensation. We also demonstrate that on the lubricant-impregnated surfaces, the choice of lubricant and underlying surface texture play a crucial role in stabilizing the lubricant and reducing pinning of the condensate. With properly engineered surfaces to promote dropwise condensation of low-surface tension fluids, we demonstrate a four to eight-fold improvement in the heat transfer coefficient.

Original languageEnglish (US)
Article number4158
JournalScientific reports
Volume4
DOIs
StatePublished - Mar 5 2014

ASJC Scopus subject areas

  • General

Fingerprint Dive into the research topics of 'Dropwise condensation of low surface tension fluids on omniphobic surfaces'. Together they form a unique fingerprint.

Cite this