Two-phase pressure drop and flow visualization of FC-72 in a silicon microchannel heat sink

Ayman Megahed, Ibrahim Hassan

Research output: Contribution to journalArticle

33 Citations (Scopus)

Abstract

The rapid development of two-phase microfluidic devices has triggered the demand for a detailed understanding of the flow characteristics inside microchannel heat sinks to advance the cooling process of micro-electronics. The present study focuses on the experimental investigation of pressure drop characteristics and flow visualization of a two-phase flow in a silicon microchannel heat sink. The microchannel heat sink consists of a rectangular silicon chip in which 45 rectangular microchannels were chemically etched with a depth of 276 μm, width of 225 μm, and a length of 16 mm. Experiments are carried out for mass fluxes ranging from 341 to 531 kg/m2 s and heat fluxes from 60.4 to 130.6 kW/m2 using FC-72 as the working fluid. Bubble growth and flow regimes are observed using high speed visualization. Three major flow regimes are identified: bubbly, slug, and annular. The frictional two-phase pressure drop increases with exit quality for a constant mass flux. An assessment of various pressure drop correlations reported in the literature is conducted for validation. A new general correlation is developed to predict the two-phase pressure drop in microchannel heat sinks for five different refrigerants. The experimental pressure drops for laminar-liquid laminar-vapor and laminar-liquid turbulent-vapor flow conditions are predicted by the new correlation with mean absolute errors of 10.4% and 14.5%, respectively.

Original languageEnglish
Pages (from-to)1171-1182
Number of pages12
JournalInternational Journal of Heat and Fluid Flow
Volume30
Issue number6
DOIs
Publication statusPublished - Dec 2009
Externally publishedYes

Fingerprint

flow visualization
heat sinks
Heat sinks
Silicon
Flow visualization
microchannels
Microchannels
pressure drop
Pressure drop
silicon
Mass transfer
Vapors
vapors
microfluidic devices
working fluids
refrigerants
flow characteristics
Liquids
Refrigerants
two phase flow

Keywords

  • Flow visualization
  • Heat sink
  • Pressure drop
  • Two-phase flow

ASJC Scopus subject areas

  • Mechanical Engineering
  • Condensed Matter Physics
  • Fluid Flow and Transfer Processes

Cite this

Two-phase pressure drop and flow visualization of FC-72 in a silicon microchannel heat sink. / Megahed, Ayman; Hassan, Ibrahim.

In: International Journal of Heat and Fluid Flow, Vol. 30, No. 6, 12.2009, p. 1171-1182.

Research output: Contribution to journalArticle

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