Analytical modeling of annular flow boiling heat transfer in mini-and microchannel heat sinks

A. Megahed, Ibrahim Hassan

Research output: Contribution to journalArticle

7 Citations (Scopus)

Abstract

An analytical model is proposed to predict the flow boiling heat transfer coefficient in the annular flow regime in mini-and microchannel heat sinks based on the separated model. The modeling procedure includes a formulation for determining the heat transfer coefficient based on the wall shear stress and the local thermophysical characteristics of the fluid based on the Reynolds' analogy. The frictional and acceleration pressure gradients within the channel are incorporated into the present model to provide a better representation of the flow conditions. The model is validated against collected data sets from the literature produced by different authors under different experimental conditions, different fluids, and with mini-and microchannels of hydraulic diameters falling within the range of 92-1440 μm. The accuracy between the experimental and predicted results is achieved with a mean absolute error of 10%. The present analytical model can correctly predict the different trends of the heat transfer coefficient reported in the literature as a function of the exit quality. The predicted two-phase heat transfer coefficient is found to be very sensitive to changes in mass flux and saturation temperature. However, it is found to be mildly sensitive to the change in heat flux.

Original languageEnglish
Pages (from-to)1-11
Number of pages11
JournalJournal of Heat Transfer
Volume132
Issue number4
DOIs
Publication statusPublished - Apr 2010
Externally publishedYes

Fingerprint

annular flow
heat sinks
Heat sinks
microchannels
Microchannels
boiling
Boiling liquids
Heat transfer coefficients
heat transfer coefficients
heat transfer
Heat transfer
Analytical models
Fluids
Pressure gradient
fluids
Heat flux
Shear stress
pressure gradients
Mass transfer
falling

Keywords

  • Annular flow
  • Mini-and microchannel heat sinks
  • Two-phase flow
  • Two-phase heat transfer coefficient

ASJC Scopus subject areas

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

Cite this

Analytical modeling of annular flow boiling heat transfer in mini-and microchannel heat sinks. / Megahed, A.; Hassan, Ibrahim.

In: Journal of Heat Transfer, Vol. 132, No. 4, 04.2010, p. 1-11.

Research output: Contribution to journalArticle

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