Anisotropic electro-osmotic flow over superhydrophobic surfaces
Patterned surfaces with large effective slip lengths, such as super-hydrophobic surfaces containing trapped gas bubbles, have the potential to greatly enhance electrokinetic phenomena. Existing theories assume either homogeneous flat surfaces or patterned surfaces with thin double layers (compared w...
| Main Authors: | , , |
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| Format: | Article |
| Language: | en_US |
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Cambridge University Press
2011
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| Online Access: | http://hdl.handle.net/1721.1/60963 |
| _version_ | 1811091885064716288 |
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| author | Bazant, Martin Z. Bahga, Supreet S. Vinogradova, Olga I. |
| author2 | Massachusetts Institute of Technology. Department of Chemical Engineering |
| author_facet | Massachusetts Institute of Technology. Department of Chemical Engineering Bazant, Martin Z. Bahga, Supreet S. Vinogradova, Olga I. |
| author_sort | Bazant, Martin Z. |
| collection | MIT |
| description | Patterned surfaces with large effective slip lengths, such as super-hydrophobic surfaces containing trapped gas bubbles, have the potential to greatly enhance electrokinetic phenomena. Existing theories assume either homogeneous flat surfaces or patterned surfaces with thin double layers (compared with the texture correlation length) and thus predict simple surface-averaged, isotropic flows (independent of orientation). By analysing electro-osmotic flows over striped slip-stick surfaces with arbitrary double-layer thickness, we show that surface anisotropy generally leads to a tensorial electro-osmotic mobility and subtle, nonlinear averaging of surface properties. Interestingly, the electro-osmotic mobility tensor is not simply related to the hydrodynamic slip tensor, except in special cases. Our results imply that significantly enhanced electro-osmotic flows over super-hydrophobic surfaces are possible, but only with charged liquid–gas interfaces. |
| first_indexed | 2024-09-23T15:09:33Z |
| format | Article |
| id | mit-1721.1/60963 |
| institution | Massachusetts Institute of Technology |
| language | en_US |
| last_indexed | 2024-09-23T15:09:33Z |
| publishDate | 2011 |
| publisher | Cambridge University Press |
| record_format | dspace |
| spelling | mit-1721.1/609632022-09-29T13:04:51Z Anisotropic electro-osmotic flow over superhydrophobic surfaces Bazant, Martin Z. Bahga, Supreet S. Vinogradova, Olga I. Massachusetts Institute of Technology. Department of Chemical Engineering Massachusetts Institute of Technology. Department of Mathematics Bazant, Martin Z. Bazant, Martin Z. Patterned surfaces with large effective slip lengths, such as super-hydrophobic surfaces containing trapped gas bubbles, have the potential to greatly enhance electrokinetic phenomena. Existing theories assume either homogeneous flat surfaces or patterned surfaces with thin double layers (compared with the texture correlation length) and thus predict simple surface-averaged, isotropic flows (independent of orientation). By analysing electro-osmotic flows over striped slip-stick surfaces with arbitrary double-layer thickness, we show that surface anisotropy generally leads to a tensorial electro-osmotic mobility and subtle, nonlinear averaging of surface properties. Interestingly, the electro-osmotic mobility tensor is not simply related to the hydrodynamic slip tensor, except in special cases. Our results imply that significantly enhanced electro-osmotic flows over super-hydrophobic surfaces are possible, but only with charged liquid–gas interfaces. National Science Foundation (U.S.) (Contract no. DMS-0707641) 2011-02-16T18:48:34Z 2011-02-16T18:48:34Z 2010-02 2009-10 Article http://purl.org/eprint/type/JournalArticle 0022-1120 1469-7645 http://hdl.handle.net/1721.1/60963 Bahga, Supreet S., Olga I. Vinogradova, and Martin Z. Bazant. “Anisotropic electro-osmotic flow over super-hydrophobic surfaces.” Journal of Fluid Mechanics 644 (2010): 245. © Cambridge University Press 2010 en_US http://dx.doi.org/10.1017/S0022112009992771 Journal of Fluid Mechanics 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 Cambridge University Press MIT web domain |
| spellingShingle | Bazant, Martin Z. Bahga, Supreet S. Vinogradova, Olga I. Anisotropic electro-osmotic flow over superhydrophobic surfaces |
| title | Anisotropic electro-osmotic flow over superhydrophobic surfaces |
| title_full | Anisotropic electro-osmotic flow over superhydrophobic surfaces |
| title_fullStr | Anisotropic electro-osmotic flow over superhydrophobic surfaces |
| title_full_unstemmed | Anisotropic electro-osmotic flow over superhydrophobic surfaces |
| title_short | Anisotropic electro-osmotic flow over superhydrophobic surfaces |
| title_sort | anisotropic electro osmotic flow over superhydrophobic surfaces |
| url | http://hdl.handle.net/1721.1/60963 |
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