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Water-oil flow in square microchannels with a crossed junction

Cao, Zhen LU ; Qian, Jin Yuan LU ; Wu, Zan LU and Sunden, Bengt LU (2018) ASME 2018 5th Joint US-European Fluids Engineering Division Summer Meeting, FEDSM 2018 3.
Abstract

In the present study, water-oil flow patterns and slug hydrodynamics were experimentally studied in square glass microchannels with various hydraulic diameters (Dh = 600 µm, 400 µm, 200 µm). The aqueous phase is the continuous phase while the organic phase is the dispersed phase. The ranges of flow rates of the continuous phase and the dispersed phase are 0-200 ml/h and 0-12 ml/h, 0-120 ml/h and 0-6 ml/h, and 0-60 ml/h and 0-2 ml/h in the microchannels with Dh = 600 µm, 400 µm and 200 µm, respectively. The results show that the hydraulic diameter has significant effects on flow patterns and three main flow patterns are observed, i.e., annular flow, slug flow and droplet flow. Generally, annular flow appeared at high flow rates of the... (More)

In the present study, water-oil flow patterns and slug hydrodynamics were experimentally studied in square glass microchannels with various hydraulic diameters (Dh = 600 µm, 400 µm, 200 µm). The aqueous phase is the continuous phase while the organic phase is the dispersed phase. The ranges of flow rates of the continuous phase and the dispersed phase are 0-200 ml/h and 0-12 ml/h, 0-120 ml/h and 0-6 ml/h, and 0-60 ml/h and 0-2 ml/h in the microchannels with Dh = 600 µm, 400 µm and 200 µm, respectively. The results show that the hydraulic diameter has significant effects on flow patterns and three main flow patterns are observed, i.e., annular flow, slug flow and droplet flow. Generally, annular flow appeared at high flow rates of the dispersed phase and low flow rates of the continuous phase, while droplet flow appeared at low flow rates of the dispersed phase and high flow rates of the continuous phase. However, slug flow existed at comparable flow rates of the continuous and dispersed phases. A dimensionless analysis is carried out and a new dimensionless group including Weber number and Reynolds number is derived. The new defined dimensionless group performs well to develop a general flow pattern map. In addition, slug flow hydrodynamics are investigated as well in the present study, considering the slug length and slug velocity. Based on the present experimental results, a new scaling law is proposed to predict the slug length and it shows a good agreement with the experimental results. It has been widely reported that slug velocities depend linearly on the total flow rates of the two phases, which is consistent with the present study. The linear law provides a good prediction of the experimental slug velocities but different slopes are suggested in microchannels with different hydraulic diameters.

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Please use this url to cite or link to this publication:
author
organization
publishing date
type
Chapter in Book/Report/Conference proceeding
publication status
published
subject
keywords
Flow pattern, Liquid-liquid flow, Microchannel, Slug hydrodynamics
host publication
Fluid Machinery; Erosion, Slurry, Sedimentation; Experimental, Multiscale, and Numerical Methods for Multiphase Flows; Gas-Liquid, Gas-Solid, and Liquid-Solid Flows; Performance of Multiphase Flow Systems; Micro/Nano-Fluidics
volume
3
publisher
American Society of Mechanical Engineers(ASME)
conference name
ASME 2018 5th Joint US-European Fluids Engineering Division Summer Meeting, FEDSM 2018
conference location
Montreal, Canada
conference dates
2018-07-15 - 2018-07-20
external identifiers
  • scopus:85056181306
ISBN
9780791851579
DOI
10.1115/FEDSM2018-83056
language
English
LU publication?
yes
id
7d9b509a-788a-4944-8a3d-e6b71fa8c5e2
date added to LUP
2018-11-23 08:44:51
date last changed
2019-02-20 11:37:27
@inproceedings{7d9b509a-788a-4944-8a3d-e6b71fa8c5e2,
  abstract     = {<p>In the present study, water-oil flow patterns and slug hydrodynamics were experimentally studied in square glass microchannels with various hydraulic diameters (Dh = 600 µm, 400 µm, 200 µm). The aqueous phase is the continuous phase while the organic phase is the dispersed phase. The ranges of flow rates of the continuous phase and the dispersed phase are 0-200 ml/h and 0-12 ml/h, 0-120 ml/h and 0-6 ml/h, and 0-60 ml/h and 0-2 ml/h in the microchannels with Dh = 600 µm, 400 µm and 200 µm, respectively. The results show that the hydraulic diameter has significant effects on flow patterns and three main flow patterns are observed, i.e., annular flow, slug flow and droplet flow. Generally, annular flow appeared at high flow rates of the dispersed phase and low flow rates of the continuous phase, while droplet flow appeared at low flow rates of the dispersed phase and high flow rates of the continuous phase. However, slug flow existed at comparable flow rates of the continuous and dispersed phases. A dimensionless analysis is carried out and a new dimensionless group including Weber number and Reynolds number is derived. The new defined dimensionless group performs well to develop a general flow pattern map. In addition, slug flow hydrodynamics are investigated as well in the present study, considering the slug length and slug velocity. Based on the present experimental results, a new scaling law is proposed to predict the slug length and it shows a good agreement with the experimental results. It has been widely reported that slug velocities depend linearly on the total flow rates of the two phases, which is consistent with the present study. The linear law provides a good prediction of the experimental slug velocities but different slopes are suggested in microchannels with different hydraulic diameters.</p>},
  author       = {Cao, Zhen and Qian, Jin Yuan and Wu, Zan and Sunden, Bengt},
  isbn         = {9780791851579},
  keyword      = {Flow pattern,Liquid-liquid flow,Microchannel,Slug hydrodynamics},
  language     = {eng},
  location     = {Montreal, Canada},
  publisher    = {American Society of Mechanical Engineers(ASME)},
  title        = {Water-oil flow in square microchannels with a crossed junction},
  url          = {http://dx.doi.org/10.1115/FEDSM2018-83056},
  volume       = {3},
  year         = {2018},
}