eprintid: 1349518
rev_number: 43
eprint_status: archive
userid: 608
dir: disk0/01/34/95/18
datestamp: 2012-06-20 18:37:23
lastmod: 2021-09-26 22:12:06
status_changed: 2012-06-20 18:37:23
type: article
metadata_visibility: show
item_issues_count: 0
creators_name: Dore, V
creators_name: Tsaoulidis, D
creators_name: Angeli, P
title: Mixing patterns in water plugs during water/ionic liquid segmented flow in microchannels
ispublished: pub
divisions: UCL
divisions: B04
divisions: C05
divisions: F43
keywords: Multiphase flow, Microfluidics, Mixing, Liquid-liquid, Ionic liquids, PIV
note: This is an open-access article distributed under the terms of the Creative Commons Attribution License (CC BY), which permits unrestricted use, distribution, and reproduction in any medium, provided the original author and source are credited.
abstract: Circulation patterns and mixing characteristics within water plugs in liquid/liquid segmented flow were investigated by means of micro-Particle Image Velocimetry. Experiments were carried out in a glass microchannel with circular cross-section of 100 μm radius using [C4mim][NTf2] ionic liquid as the carrier fluid. A T-junction was used as inlet, while mixture velocities varied from 0.0028 m/s to 0.0674 m/s. Two main circulation vortices were found within the plugs while at intermediate mixture velocities two additional secondary vortices appeared at the plug front. The mixing rate was locally quantified by means of the non-dimensional circulation time, which was calculated across the plug length. Consistently with the circulation patterns, the non-dimensional circulation time was found to have a profile along the direction of the flow that mirrors the shape of the plug, with a minimum at the axial location of the vortex cores (where the circulation velocity is maximum at the channel centre) while it tended to infinity towards the liquid/liquid interfaces. For all the experiments the minimum value of the circulation time fell within the range of 1.00–1.75. For increasing mixture velocities (i.e. increasing Ca) and sufficiently long plugs (εIL=0.4) a general decrease (i.e. higher mixing rate) of the circulation time minimum was found, although the behaviour was rather complex. On the other hand, the circulation velocity linearly increased as the Ca number (mixture velocity) increased.
date: 2012-10-01
official_url: http://dx.doi.org/10.1016/j.ces.2012.06.030
vfaculties: VENG
oa_status: green
language: eng
primo: open
primo_central: open_green
verified: verified_manual
elements_source: WoS-Lite
elements_id: 415196
doi: 10.1016/j.ces.2012.06.030
lyricists_name: Angeli, Panagiota
lyricists_name: Dore, Valentina
lyricists_name: Tsaoulidis, Dimitrios
lyricists_id: PANGE44
lyricists_id: VDORE38
lyricists_id: DTSAO84
full_text_status: public
publication: Chemical Engineering Science
volume: 80
pagerange: 334 - 341
issn: 0009-2509
citation:        Dore, V;    Tsaoulidis, D;    Angeli, P;      (2012)    Mixing patterns in water plugs during water/ionic liquid segmented flow in microchannels.                   Chemical Engineering Science , 80    334 - 341.    10.1016/j.ces.2012.06.030 <https://doi.org/10.1016/j.ces.2012.06.030>.       Green open access   
 
document_url: https://discovery.ucl.ac.uk/id/eprint/1349518/1/1349518.pdf