Flow Patterns Transition Criteria from Bubbly to Slug Flow during Flow Boiling in Confined Vertical Narrow Rectangular Channels

Abstract:

To investigate new features of flow patterns transition during flow boiling in confined vertical narrow rectangular channels, both experiments and theoretical analysis were carried out in the present study. When the channel size was smaller than the bubble departure diameter, a new flow pattern was observed and defined as “confined bubbly flow”. According to the relative size between bubble departure diameter and channel size, two groups of flow pattern transition criteria were developed by using modified drift flux model, with taking features of flow boiling and narrow confinement into account. Satisfactory agreement was obtained by compare model prediction with experiment results. However, further verification and modification are still needed for wider applications.

• Periodical: Applied Mechanics and Materials (Volumes 155-156)
• Pages: 616-620
• DOI: https://doi.org/10.4028/www.scientific.net/AMM.155-156.616
• Online since: February 2012
• Authors: Wei Chang, Shu Sheng Zhang, Can Zhao, Yun Li Zhang
• Keywords: Bubble Departure Diameter, Confined Bubbly Flow, Drift Flux Model, Narrow Channel

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