0

Full Content is available to subscribers

Subscribe/Learn More  >

Characteristics of Pool Boiling Bubble Dynamics in Bead Packed Porous Structures

[+] Author Affiliations
Calvin H. Li, Ting Li, Paul Hodgins

University of Toledo, Toledo, OH

G. P. Peterson

Georgia Institute of Technology, Atlanta, GA

Paper No. HT2009-88041, pp. 561-577; 17 pages
doi:10.1115/HT2009-88041
From:
  • ASME 2009 Heat Transfer Summer Conference collocated with the InterPACK09 and 3rd Energy Sustainability Conferences
  • Volume 3: Combustion, Fire and Reacting Flow; Heat Transfer in Multiphase Systems; Heat Transfer in Transport Phenomena in Manufacturing and Materials Processing; Heat and Mass Transfer in Biotechnology; Low Temperature Heat Transfer; Environmental Heat Transfer; Heat Transfer Education; Visualization of Heat Transfer
  • San Francisco, California, USA, July 19–23, 2009
  • Conference Sponsors: Heat Transfer Division
  • ISBN: 978-0-7918-4358-1 | eISBN: 978-0-7918-3851-8
  • Copyright © 2009 by ASME

abstract

Spherical glass and copper beads have been used to create bead packed porous structures for an investigation of two-phase heat transfer bubble dynamics under geometric constraints. The results demonstrated a variety of bubble dynamics characteristics under a range of heating conditions. At low heat flux of 18.9 kW/m2 , a single spherical bubble formed at nucleation sites of a heating surface and departed to the interstitial spaces of porous structure. When heat flux increased to 47 kW/m2 , a single bubble grew into a Y shape between beads layers and connected with others to generate a horizontal vapor column. As heat flux reached 76.3 kW/m2 , vertical vapor columns obtained strong momentum to form several major vapor escaping arteries, and glass beads were pushed upward by the vapor in the escaping arteries. According to Zuber’s hydrodynamics theory, choking will take place when the size of vapor columns reaches a certain value that is comparable to the critical hydrodynamic wavelength of the vapor column in plain surface pool boiling. The experimental and simulation results of this investigation illustrated that, under the geometric constrains of bead packed porous structures, similar characteristics had been induced to trigger the earlier occurrence of vapor column chocking inside porous structures. The bubble generation, growth, and detachment during the nucleate pool boiling heat transfer have been filmed, the heating surface temperatures and heat flux were recorded, and theoretical models have been employed to study bubble dynamic characteristics. Computer simulation results were combined with experimental observations to clarify the details of the vapor bubble growth process and the liquid water replenishing the inside of the porous structures. This investigation has clearly shown, with both experimental and computer simulation evidence, that the millimeter scale bead packed porous structures could greatly influence pool boiling heat transfer by forcing a single bubble to depart at a smaller size as compared to that in a plain surface situation at low heat flux situations, and could trigger the earlier occurrence of critical heat flux (CHF) by trapping the vapor into interstitial space and forming a vapor column net. The results also proved data for further development of theoretical models of pool boiling heat transfer in bead packed porous structures.

Copyright © 2009 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