Investigation of boiling and bubble confinement in a high aspect ratio micro-channel

Y. Wang, K. Sefiane, R. Bennacer

Research output: Contribution to journalArticlepeer-review

Abstract

In this paper we experimentally investigated the pressure drop fluctuation and liquid/vapour interface behaviours during flow boiling in a single rectangular micro-channel with high aspect ratio. An integrated testing system including syringe pump, pressure sensors, thermocouples, micro-channel and high speed camera was mounted in a 1 m x 1 m x 1 m plexiglass box, the ambient temperature inside of which was controllable. A micro-channel with the hydraulic diameter of 727 mu m was chosen, the aspect ratio of which was 10. FC-72 was used as the working liquid, with a saturation temperature of 56 C at atmospheric pressure.

The present study concentrated on the transition from single-phase flow to two-phase flow (including single-phase friction losses and onset of nucleation) and flow instabilities and liquid vapour interface behaviors during two-phase flow. Pressures at inlet (P-in) and outlet (P-out) of the channel were measured and pressure drop (P-in - P-out) was then obtained. The pressure drop fluctuation was discussed. Besides, various liquid vapour interface behaviors including interface deformation, recoiling and re-wetting as well as bubble nucleation, bubble growth and bubble geometry were captured and analyzed with the aid of a high speed camera. Additionally, evaporation rates of bubble nose and bubble tail at different mass fluxes and heat fluxes were compared. (C) 2010 Elsevier Ltd. All rights reserved.

Original languageEnglish
Pages (from-to)610-618
Number of pages9
JournalApplied Thermal Engineering
Volume31
Issue number5
DOIs
Publication statusPublished - Apr 2011

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