Share

IIR document

Flow regimes of R32, R1234yf, and R454C in horizontal multiport mini/ micro-channels: Development of a new flow regime prediction method.

Author(s) : NOGAMI T., JIGE D., INOUE N.

Type of article: IJR article

Summary

This study investigates the two-phase flow structures of a zeotropic binary refrigerant mixture (R454C) and two pure refrigerants (R32 and R1234yf) in multiport square mini/micro-channels with hydraulic diameters of 0.5 and 1.0 mm. Flow visualization experiments were conducted to examine the effects of the channel size, refrigerant pressure, and thermophysical properties on flow regime transitions. Three primary flow regimes were identified: plug (intermittent), slug-annular, and annular flows. As the hydraulic diameter decreased, the transition boundary from plug flow to slug-annular flow (P/SA) shifted towards higher vapor quality and mass flux, while the transition boundary from slug-annular flow to annular flow (SA/A) moved toward higher values of both parameters. Similarly, the P/SA and SA/A transition boundaries shifted towards slightly higher vapor quality and mass flux as the refrigerant pressure increased. The observed results were compared with existing flow regime maps. A new flow regime map was proposed, incorporating transition boundaries defined by the Weber number, Reynolds number, and confinement number. This new flow regime map achieved a prediction accuracy of 93.9 %. The accuracy of the flow regime maps was validated using previously reported data for different hydraulic diameter, refrigerants, and saturation pressures.

Available documents

Format PDF

Pages: 12 p.

Available

  • Public price

    20 €

  • Member price*

    Free

* Best rate depending on membership category (see the detailed benefits of individual and corporate memberships).

Details

  • Original title: Flow regimes of R32, R1234yf, and R454C in horizontal multiport mini/ micro-channels: Development of a new flow regime prediction method.
  • Record ID : 30034357
  • Languages: English
  • Subject: Technology
  • Source: International Journal of Refrigeration - Revue Internationale du Froid - vol. 179
  • Publication date: 2025/11
  • DOI: http://dx.doi.org/https://doi.org/10.1016/j.ijrefrig.2025.08.015

Links


See other articles in this issue (29)
See the source

Indexing