Research Papers: Micro/Nanoscale Heat Transfer

Critical Heat Flux of Water at Subatmospheric Pressures in Microchannels

[+] Author and Article Information
C.-J. Kuo

Department of Mechanical, Aerospace, and Nuclear Engineering,  Rensselaer Polytechnic Institute, Troy, NY 12180

Y. Peles1

Department of Mechanical, Aerospace, and Nuclear Engineering,  Rensselaer Polytechnic Institute, Troy, NY 12180pelesy@rpi.edu


Corresponding author.

J. Heat Transfer 130(7), 072403 (May 20, 2008) (7 pages) doi:10.1115/1.2909077 History: Received April 09, 2007; Revised July 31, 2007; Published May 20, 2008

Critical heat flux conditions for water at subatmospheric pressures in an array of silicon-based, 227μm hydraulic diameter, rectangular microchannels were experimentally studied. Experiments were conducted at exit pressures from 0.1atmto1atm, mass fluxes from 86kgm2sto303kgm2s, and an effective heat flux up to 444Wcm2. The annular flow pattern revealed during flow visualization and the high exit qualities at CHF conditions suggest dryout to be the CHF mechanism. An analysis, based on the experimental results and known CHF characteristics, on the dependency of the critical heat flux on various variables was performed. It was found that the boiling number at the CHF condition was approximately a constant.

Copyright © 2008 by American Society of Mechanical Engineers
Your Session has timed out. Please sign back in to continue.



Grahic Jump Location
Figure 1

The ratio of the highest measured CHF to the maximum heat flux from the kinetic theory, qCHF″∕qmkv″, as a function of dimensionless exit pressure, pe∕pc

Grahic Jump Location
Figure 2

(a) A CAD model of the microdevice; (b) geometry of the inlet orifice configuration (all units in μm)

Grahic Jump Location
Figure 3

Experiment setup

Grahic Jump Location
Figure 4

Characteristic flow boiling morphologies

Grahic Jump Location
Figure 5

(a) The exit mass quality at CHF conditions as a function of mass flux; (b) CHF as a function of mass quality

Grahic Jump Location
Figure 6

CHF as a function of mass flux

Grahic Jump Location
Figure 7

The boiling number at CHF conditions as a function of liquid-to-vapor density ratio, ρl∕ρv




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 Journal Articles
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