Effect of cross-sectional perturbation on critical heat flux criteria in microchannels

Mark J. Miner, Patrick Phelan

2 Scopus citations


A variety of predictive correlations for critical heat flux (CHF) are examined in light of the growing body of work exploring enhanced flow boiling CHF via cross-sectional expansion. The analysis considers the effect of a small perturbation of the diameter of a circular microchannel on the predictions made by the selected criteria, and seeks to demonstrate an optimum rate of expansion. It is demonstrated that a nonzero diameter expansion necessarily improves performance under several criteria for critical heat flux, and an optimum expansion rate exists for many of these criteria. CHF relations are seen to follow a few distinct types, and those relations which contemplate effects which may directly influence CHF, such as pressure and phase velocity, tend to better reflect the experimentally demonstrated effect of the expanding channel diameter on CHF. Experimental data are examined from several investigators, including the authors' group, and the validity of both the criteria and the analysis is compared to the data.

Original languageEnglish (US)
Article number101009
JournalJournal of Heat Transfer
Issue number10
Publication statusPublished - 2013



  • critical heat flux
  • expanding cross-section
  • flow boiling
  • heat transfer
  • microchannel
  • perturbation

ASJC Scopus subject areas

  • Mechanical Engineering
  • Mechanics of Materials
  • Materials Science(all)
  • Condensed Matter Physics

Cite this

Effect of cross-sectional perturbation on critical heat flux criteria in microchannels. / Miner, Mark J.; Phelan, Patrick.

In: Journal of Heat Transfer, Vol. 135, No. 10, 101009, 2013.

Research output: Contribution to journalArticle