Numerical investigation of nanostructure orientation on electroosmotic flow
Electroosmotic flow (EOF) is fluid flow induced by an applied electric field, which has been widely employed in various micro-/nanofluidic applications. Past investigations have revealed that the presence of nanostructures in microchannel reduces EOF. Hitherto, the angle-dependent behavior of nanoli...
| Main Authors: | , |
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| Other Authors: | |
| Format: | Journal Article |
| Language: | English |
| Published: |
2020
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| Online Access: | https://hdl.handle.net/10356/145363 |
| _version_ | 1826125537914912768 |
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| author | Lim, An Eng Lam, Yee Cheong |
| author2 | School of Mechanical and Aerospace Engineering |
| author_facet | School of Mechanical and Aerospace Engineering Lim, An Eng Lam, Yee Cheong |
| author_sort | Lim, An Eng |
| collection | NTU |
| description | Electroosmotic flow (EOF) is fluid flow induced by an applied electric field, which has been widely employed in various micro-/nanofluidic applications. Past investigations have revealed that the presence of nanostructures in microchannel reduces EOF. Hitherto, the angle-dependent behavior of nanoline structures on EOF has not yet been studied in detail and its understanding is lacking. Numerical analyses of the effect of nanoline orientation angle θ on EOF to reveal the associated mechanisms were conducted in this investigation. When θ increases from 5° to 90° (from parallel to perpendicular to the flow direction), the average EOF velocity decreases exponentially due to the increase in distortion of the applied electric field distribution at the structured surface, as a result of the increased apparent nanolines per unit microchannel length. With increasing nanoline width W, the decrease of average EOF velocity is fairly linear, attributed to the simultaneous narrowing of nanoline ridge (high local fluid velocity region). While increasing nanoline depth D results in a monotonic decrease of the average EOF velocity. This reduction stabilizes for aspect ratio D/W > 0.5 as the electric field distribution distortion within the nanoline trench remains nearly constant. This investigation reveals that the effects on EOF of nanolines, and by extrapolation for any nanostructures, may be directly attributed to their effects on the distortion of the applied electric field distribution within a microchannel. |
| first_indexed | 2024-10-01T06:37:57Z |
| format | Journal Article |
| id | ntu-10356/145363 |
| institution | Nanyang Technological University |
| language | English |
| last_indexed | 2024-10-01T06:37:57Z |
| publishDate | 2020 |
| record_format | dspace |
| spelling | ntu-10356/1453632023-03-04T17:12:20Z Numerical investigation of nanostructure orientation on electroosmotic flow Lim, An Eng Lam, Yee Cheong School of Mechanical and Aerospace Engineering Engineering::Mechanical engineering Electrokinetic Phenomenon Electroosmotic Flow Electroosmotic flow (EOF) is fluid flow induced by an applied electric field, which has been widely employed in various micro-/nanofluidic applications. Past investigations have revealed that the presence of nanostructures in microchannel reduces EOF. Hitherto, the angle-dependent behavior of nanoline structures on EOF has not yet been studied in detail and its understanding is lacking. Numerical analyses of the effect of nanoline orientation angle θ on EOF to reveal the associated mechanisms were conducted in this investigation. When θ increases from 5° to 90° (from parallel to perpendicular to the flow direction), the average EOF velocity decreases exponentially due to the increase in distortion of the applied electric field distribution at the structured surface, as a result of the increased apparent nanolines per unit microchannel length. With increasing nanoline width W, the decrease of average EOF velocity is fairly linear, attributed to the simultaneous narrowing of nanoline ridge (high local fluid velocity region). While increasing nanoline depth D results in a monotonic decrease of the average EOF velocity. This reduction stabilizes for aspect ratio D/W > 0.5 as the electric field distribution distortion within the nanoline trench remains nearly constant. This investigation reveals that the effects on EOF of nanolines, and by extrapolation for any nanostructures, may be directly attributed to their effects on the distortion of the applied electric field distribution within a microchannel. Nanyang Technological University Published version The authors gratefully acknowledge Nanyang Technological University (NTU) for its financial support (Grant no. M4081926). 2020-12-18T06:13:05Z 2020-12-18T06:13:05Z 2020 Journal Article Lim, A. E., & Lam, Y. C. (2020). Numerical investigation of nanostructure orientation on electroosmotic flow. Micromachines, 11(11), 971-. doi:10.3390/mi11110971 2072-666X https://hdl.handle.net/10356/145363 10.3390/mi11110971 33138301 11 11 en M4081926 Micromachines © 2020 The Authors. Licensee MDPI, Basel, Switzerland. This article is an open access article distributed under the terms and conditions of the Creative Commons Attribution (CC BY) license (http://creativecommons.org/licenses/by/4.0/). application/pdf |
| spellingShingle | Engineering::Mechanical engineering Electrokinetic Phenomenon Electroosmotic Flow Lim, An Eng Lam, Yee Cheong Numerical investigation of nanostructure orientation on electroosmotic flow |
| title | Numerical investigation of nanostructure orientation on electroosmotic flow |
| title_full | Numerical investigation of nanostructure orientation on electroosmotic flow |
| title_fullStr | Numerical investigation of nanostructure orientation on electroosmotic flow |
| title_full_unstemmed | Numerical investigation of nanostructure orientation on electroosmotic flow |
| title_short | Numerical investigation of nanostructure orientation on electroosmotic flow |
| title_sort | numerical investigation of nanostructure orientation on electroosmotic flow |
| topic | Engineering::Mechanical engineering Electrokinetic Phenomenon Electroosmotic Flow |
| url | https://hdl.handle.net/10356/145363 |
| work_keys_str_mv | AT limaneng numericalinvestigationofnanostructureorientationonelectroosmoticflow AT lamyeecheong numericalinvestigationofnanostructureorientationonelectroosmoticflow |