Shear Flow of an Electrically Charged Fluid by Ion Concentration Polarization: Scaling Laws for Electroconvective Vortices
We consider electroconvective fluid flows initiated by ion concentration polarization (ICP) under pressure-driven shear flow, a scenario often found in many electrochemical devices and systems. Combining scaling analysis, experiment, and numerical modeling, we reveal unique behaviors of ICP under sh...
| Main Authors: | , , , |
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| Format: | Article |
| Language: | en_US |
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American Physical Society
2013
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| Online Access: | http://hdl.handle.net/1721.1/79575 https://orcid.org/0000-0001-7215-1439 |
| _version_ | 1811081568922370048 |
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| author | Kwak, Rhokyun Pham, Van Sang Lim, Kian Meng Han, Jongyoon |
| author2 | Massachusetts Institute of Technology. Department of Biological Engineering |
| author_facet | Massachusetts Institute of Technology. Department of Biological Engineering Kwak, Rhokyun Pham, Van Sang Lim, Kian Meng Han, Jongyoon |
| author_sort | Kwak, Rhokyun |
| collection | MIT |
| description | We consider electroconvective fluid flows initiated by ion concentration polarization (ICP) under pressure-driven shear flow, a scenario often found in many electrochemical devices and systems. Combining scaling analysis, experiment, and numerical modeling, we reveal unique behaviors of ICP under shear flow: a unidirectional vortex structure, its height selection, and vortex advection. Determined by both the external pressure gradient and the electric body force, the dimensionless height of the sheared electroconvective vortex is shown to scale as (ϕ[superscript 2]/U[subscript HP])[superscript 1/3], which is a clear departure from the previous diffusion-drift model prediction. To the best of our knowledge, this is the first microscopic characterization of ion concentration polarization under shear flow, and it firmly establishes electroconvection as the mechanism for an overlimiting current in realistic, large-area ion exchange membrane systems such as electrodialysis. The new scaling law has significant implications on the optimization of electrodialysis and other electrochemical systems. |
| first_indexed | 2024-09-23T11:48:42Z |
| format | Article |
| id | mit-1721.1/79575 |
| institution | Massachusetts Institute of Technology |
| language | en_US |
| last_indexed | 2024-09-23T11:48:42Z |
| publishDate | 2013 |
| publisher | American Physical Society |
| record_format | dspace |
| spelling | mit-1721.1/795752022-10-01T06:11:58Z Shear Flow of an Electrically Charged Fluid by Ion Concentration Polarization: Scaling Laws for Electroconvective Vortices Kwak, Rhokyun Pham, Van Sang Lim, Kian Meng Han, Jongyoon Massachusetts Institute of Technology. Department of Biological Engineering Massachusetts Institute of Technology. Department of Electrical Engineering and Computer Science Massachusetts Institute of Technology. Department of Mechanical Engineering Kwak, Rhokyun Han, Jongyoon We consider electroconvective fluid flows initiated by ion concentration polarization (ICP) under pressure-driven shear flow, a scenario often found in many electrochemical devices and systems. Combining scaling analysis, experiment, and numerical modeling, we reveal unique behaviors of ICP under shear flow: a unidirectional vortex structure, its height selection, and vortex advection. Determined by both the external pressure gradient and the electric body force, the dimensionless height of the sheared electroconvective vortex is shown to scale as (ϕ[superscript 2]/U[subscript HP])[superscript 1/3], which is a clear departure from the previous diffusion-drift model prediction. To the best of our knowledge, this is the first microscopic characterization of ion concentration polarization under shear flow, and it firmly establishes electroconvection as the mechanism for an overlimiting current in realistic, large-area ion exchange membrane systems such as electrodialysis. The new scaling law has significant implications on the optimization of electrodialysis and other electrochemical systems. National Science Foundation (U.S.) (CBET-0854026) United States. Defense Advanced Research Projects Agency (Cipher program) Singapore-MIT Alliance (CE programme) 2013-07-10T20:23:51Z 2013-07-10T20:23:51Z 2013-03 2012-07 Article http://purl.org/eprint/type/JournalArticle 0031-9007 1079-7114 http://hdl.handle.net/1721.1/79575 Kwak, Rhokyun, Van Sang Pham, Kian Meng Lim, and Jongyoon Han. Shear Flow of an Electrically Charged Fluid by Ion Concentration Polarization: Scaling Laws for Electroconvective Vortices. Physical Review Letters 110, no. 11 (March 2013). © 2013 American Physical Society https://orcid.org/0000-0001-7215-1439 en_US http://dx.doi.org/10.1103/PhysRevLett.110.114501 Physical Review Letters Article is made available in accordance with the publisher's policy and may be subject to US copyright law. Please refer to the publisher's site for terms of use. application/pdf American Physical Society APS |
| spellingShingle | Kwak, Rhokyun Pham, Van Sang Lim, Kian Meng Han, Jongyoon Shear Flow of an Electrically Charged Fluid by Ion Concentration Polarization: Scaling Laws for Electroconvective Vortices |
| title | Shear Flow of an Electrically Charged Fluid by Ion Concentration Polarization: Scaling Laws for Electroconvective Vortices |
| title_full | Shear Flow of an Electrically Charged Fluid by Ion Concentration Polarization: Scaling Laws for Electroconvective Vortices |
| title_fullStr | Shear Flow of an Electrically Charged Fluid by Ion Concentration Polarization: Scaling Laws for Electroconvective Vortices |
| title_full_unstemmed | Shear Flow of an Electrically Charged Fluid by Ion Concentration Polarization: Scaling Laws for Electroconvective Vortices |
| title_short | Shear Flow of an Electrically Charged Fluid by Ion Concentration Polarization: Scaling Laws for Electroconvective Vortices |
| title_sort | shear flow of an electrically charged fluid by ion concentration polarization scaling laws for electroconvective vortices |
| url | http://hdl.handle.net/1721.1/79575 https://orcid.org/0000-0001-7215-1439 |
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