Electroosmotic flow hysteresis for dissimilar ionic solutions
Electroosmotic flow (EOF) with two or more fluids is commonly encountered in various microfluidics applications. However, no investigation has hitherto been conducted to investigate the hysteretic or flow direction-dependent behavior during the displacement flow of solutions with dissimilar ionic sp...
Saved in:
Main Authors: | , , |
---|---|
Other Authors: | |
Format: | Article |
Language: | English |
Published: |
2015
|
Subjects: | |
Online Access: | https://hdl.handle.net/10356/107168 http://hdl.handle.net/10220/25458 |
Tags: |
Add Tag
No Tags, Be the first to tag this record!
|
Institution: | Nanyang Technological University |
Language: | English |
id |
sg-ntu-dr.10356-107168 |
---|---|
record_format |
dspace |
spelling |
sg-ntu-dr.10356-1071682023-03-04T17:15:14Z Electroosmotic flow hysteresis for dissimilar ionic solutions Lim, An Eng Lim, Chun Yee Lam, Yee Cheong School of Mechanical and Aerospace Engineering DRNTU::Engineering::Mechanical engineering::Fluid mechanics Electroosmotic flow (EOF) with two or more fluids is commonly encountered in various microfluidics applications. However, no investigation has hitherto been conducted to investigate the hysteretic or flow direction-dependent behavior during the displacement flow of solutions with dissimilar ionic species. In this investigation, electroosmotic displacement flow involving dissimilar ionic solutions was studied experimentally through a current monitoring method and numerically through finite element simulations. The flow hysteresis can be characterized by the turning and displacement times; turning time refers to the abrupt gradient change of current-time curve while displacement time is the time for one solution to completely displace the other solution. Both experimental and simulation results illustrate that the turning and displacement times for a particular solution pair can be directional-dependent, indicating that the flow conditions in the microchannel are not the same in the two different flow directions. The mechanics of EOF hysteresis was elucidated through the theoretical model which includes the ionic mobility of each species, a major governing parameter. Two distinct mechanics have been identified as the causes for the EOF hysteresis involving dissimilar ionic solutions: the widening/sharpening effect of interfacial region between the two solutions and the difference in ion concentration distributions (and thus average zeta potentials) in different flow directions. The outcome of this investigation contributes to the fundamental understanding of flow behavior in microfluidic systems involving solution pair with dissimilar ionic species. ASTAR (Agency for Sci., Tech. and Research, S’pore) Published version 2015-04-27T06:52:04Z 2019-12-06T22:25:57Z 2015-04-27T06:52:04Z 2019-12-06T22:25:57Z 2015 2015 Journal Article Lim, A. E., Lim, C. Y., & Lam, Y. C. (2015). Electroosmotic flow hysteresis for dissimilar ionic solutions. Biomicrofluidics, 9. 1932-1058(electronic) https://hdl.handle.net/10356/107168 http://hdl.handle.net/10220/25458 10.1063/1.4917386 25945139 190718 184354 en Biomicrofluidics © 2015 AIP Publishing LLC. This paper was published in Biomicrofluidics and is made available as an electronic reprint (preprint) with permission of AIP Publishing LLC. The paper can be found at the following official DOI: [http://dx.doi.org/10.1063/1.4917386]. One print or electronic copy may be made for personal use only. Systematic or multiple reproduction, distribution to multiple locations via electronic or other means, duplication of any material in this paper for a fee or for commercial purposes, or modification of the content of the paper is prohibited and is subject to penalties under law. application/pdf |
institution |
Nanyang Technological University |
building |
NTU Library |
continent |
Asia |
country |
Singapore Singapore |
content_provider |
NTU Library |
collection |
DR-NTU |
language |
English |
topic |
DRNTU::Engineering::Mechanical engineering::Fluid mechanics |
spellingShingle |
DRNTU::Engineering::Mechanical engineering::Fluid mechanics Lim, An Eng Lim, Chun Yee Lam, Yee Cheong Electroosmotic flow hysteresis for dissimilar ionic solutions |
description |
Electroosmotic flow (EOF) with two or more fluids is commonly encountered in various microfluidics applications. However, no investigation has hitherto been conducted to investigate the hysteretic or flow direction-dependent behavior during the displacement flow of solutions with dissimilar ionic species. In this investigation, electroosmotic displacement flow involving dissimilar ionic solutions was studied experimentally through a current monitoring method and numerically through finite element simulations. The flow hysteresis can be characterized by the turning and displacement times; turning time refers to the abrupt gradient change of current-time curve while displacement time is the time for one solution to completely displace the other solution. Both experimental and simulation results illustrate that the turning and displacement times for a particular solution pair can be directional-dependent, indicating that the flow conditions in the microchannel are not the same in the two different flow directions. The mechanics of EOF hysteresis was elucidated through the theoretical model which includes the ionic mobility of each species, a major governing parameter. Two distinct mechanics have been identified as the causes for the EOF hysteresis involving dissimilar ionic solutions: the widening/sharpening effect of interfacial region between the two solutions and the difference in ion concentration distributions (and thus average zeta potentials) in different flow directions. The outcome of this investigation contributes to the fundamental understanding of flow behavior in microfluidic systems involving solution pair with dissimilar ionic species. |
author2 |
School of Mechanical and Aerospace Engineering |
author_facet |
School of Mechanical and Aerospace Engineering Lim, An Eng Lim, Chun Yee Lam, Yee Cheong |
format |
Article |
author |
Lim, An Eng Lim, Chun Yee Lam, Yee Cheong |
author_sort |
Lim, An Eng |
title |
Electroosmotic flow hysteresis for dissimilar ionic solutions |
title_short |
Electroosmotic flow hysteresis for dissimilar ionic solutions |
title_full |
Electroosmotic flow hysteresis for dissimilar ionic solutions |
title_fullStr |
Electroosmotic flow hysteresis for dissimilar ionic solutions |
title_full_unstemmed |
Electroosmotic flow hysteresis for dissimilar ionic solutions |
title_sort |
electroosmotic flow hysteresis for dissimilar ionic solutions |
publishDate |
2015 |
url |
https://hdl.handle.net/10356/107168 http://hdl.handle.net/10220/25458 |
_version_ |
1759854703629303808 |