0

Full Content is available to subscribers

Subscribe/Learn More  >

Experimental and Numerical Study of Single Bubble Dynamics on a Hydrophobic Surface

[+] Author Affiliations
Youngsuk Nam, Gopinath Warrier, Jinfeng Wu, Y. Sungtaek Ju

University of California at Los Angeles, Los Angeles, CA

Paper No. IMECE2007-42461, pp. 301-307; 7 pages
doi:10.1115/IMECE2007-42461
From:
  • ASME 2007 International Mechanical Engineering Congress and Exposition
  • Volume 8: Heat Transfer, Fluid Flows, and Thermal Systems, Parts A and B
  • Seattle, Washington, USA, November 11–15, 2007
  • Conference Sponsors: ASME
  • ISBN: 0-7918-4302-5 | eISBN: 0-7918-3812-9
  • Copyright © 2007 by ASME

abstract

The growth and departure of single bubbles on two surfaces with very different wettability is studied using high-speed video microscopy and numerical simulation. Isolated artificial cavities of approximately 10μm diameter are microfabricated on a bare and a Teflon-coated silicon substrate to serve as nucleation sites. The bubble departure diameter is observed to be almost three times larger and the growth period almost 60 times longer for the hydrophobic surface than for the hydrophilic surface. The waiting period is practically zero for the hydrophobic surface because a small residual bubble nucleus is left behind on the cavity from the previous ebullition cycle. The experimental results are consistent with our numerical simulations. Bubble nucleation occurs on nominally smooth hydrophobic regions with root mean square roughness (Rq ) less than 1 nm even at superheat as small as 3 °C. Liquid subcooling significantly affects bubble growth on the hydrophobic surface due to increased bubble surface area. Fundamental understanding of bubble dynamics on heated hydrophobic surfaces will help to develop chemically patterned surfaces with enhanced boiling heat transfer and novel phase-change based micro-actuators and energy harvesters.

Copyright © 2007 by ASME

Figures

Tables

Interactive Graphics

Video

Country-Specific Mortality and Growth Failure in Infancy and Yound Children and Association With Material Stature

Use interactive graphics and maps to view and sort country-specific infant and early dhildhood mortality and growth failure data and their association with maternal

NOTE:
Citing articles are presented as examples only. In non-demo SCM6 implementation, integration with CrossRef’s "Cited By" API will populate this tab (http://www.crossref.org/citedby.html).

Some tools below are only available to our subscribers or users with an online account.

Related Content

Customize your page view by dragging and repositioning the boxes below.

Related eBook Content
Topic Collections

Sorry! You do not have access to this content. For assistance or to subscribe, please contact us:

  • TELEPHONE: 1-800-843-2763 (Toll-free in the USA)
  • EMAIL: asmedigitalcollection@asme.org
Sign In