Sustainable Drag Reduction in Turbulent Taylor-Couette Flows by Depositing Sprayable Superhydrophobic Surfaces
We demonstrate a reduction in the measured inner wall shear stress in moderately turbulent Taylor-Couette flows by depositing sprayable superhydrophobic microstructures on the inner rotor surface. The magnitude of reduction becomes progressively larger as the Reynolds number increases up to a value...
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| Format: | Article |
| Language: | English |
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American Physical Society
2015
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| Online Access: | http://hdl.handle.net/1721.1/92834 https://orcid.org/0000-0002-3873-2472 https://orcid.org/0000-0003-4591-6090 https://orcid.org/0000-0001-8323-2779 https://orcid.org/0000-0003-1085-7692 |
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| author | Srinivasan, Siddarth Gilbert, Jonathan Brian Cohen, Robert E. McKinley, Gareth H. Kleingartner, Justin Alan Milne, Andrew James Barnabas |
| author2 | Massachusetts Institute of Technology. Department of Chemical Engineering |
| author_facet | Massachusetts Institute of Technology. Department of Chemical Engineering Srinivasan, Siddarth Gilbert, Jonathan Brian Cohen, Robert E. McKinley, Gareth H. Kleingartner, Justin Alan Milne, Andrew James Barnabas |
| author_sort | Srinivasan, Siddarth |
| collection | MIT |
| description | We demonstrate a reduction in the measured inner wall shear stress in moderately turbulent Taylor-Couette flows by depositing sprayable superhydrophobic microstructures on the inner rotor surface. The magnitude of reduction becomes progressively larger as the Reynolds number increases up to a value of 22% at Re=8.0×10[superscript 4]. We show that the mean skin friction coefficient C[subscript f] in the presence of the superhydrophobic coating can be fitted to a modified Prandtl–von Karman–type relationship of the form (C[subscript f]/2)[[superscript -1/2] = Mln (Re(C[subscript f]/2)[[superscript 1/2]) + N + (b/Δr)Re(C[subscript f]/2)[superscript 1/2] from which we extract an effective slip length of b ≈ 19 μm. The dimensionless effective slip length b[superscript +] = b/δ[subscript ν], where δ[subscript ν] is the viscous length scale, is the key parameter that governs the drag reduction and is shown to scale as b[[superscript +] ~ Re[superscript 1/2] in the limit of high Re. |
| first_indexed | 2024-09-23T16:52:51Z |
| format | Article |
| id | mit-1721.1/92834 |
| institution | Massachusetts Institute of Technology |
| language | English |
| last_indexed | 2024-09-23T16:52:51Z |
| publishDate | 2015 |
| publisher | American Physical Society |
| record_format | dspace |
| spelling | mit-1721.1/928342022-10-03T08:52:58Z Sustainable Drag Reduction in Turbulent Taylor-Couette Flows by Depositing Sprayable Superhydrophobic Surfaces Srinivasan, Siddarth Gilbert, Jonathan Brian Cohen, Robert E. McKinley, Gareth H. Kleingartner, Justin Alan Milne, Andrew James Barnabas Massachusetts Institute of Technology. Department of Chemical Engineering Massachusetts Institute of Technology. Department of Mechanical Engineering Srinivasan, Siddarth Kleingartner, Justin Alan Gilbert, Jonathan Brian Cohen, Robert E. Milne, Andrew James Barnabas McKinley, Gareth H. We demonstrate a reduction in the measured inner wall shear stress in moderately turbulent Taylor-Couette flows by depositing sprayable superhydrophobic microstructures on the inner rotor surface. The magnitude of reduction becomes progressively larger as the Reynolds number increases up to a value of 22% at Re=8.0×10[superscript 4]. We show that the mean skin friction coefficient C[subscript f] in the presence of the superhydrophobic coating can be fitted to a modified Prandtl–von Karman–type relationship of the form (C[subscript f]/2)[[superscript -1/2] = Mln (Re(C[subscript f]/2)[[superscript 1/2]) + N + (b/Δr)Re(C[subscript f]/2)[superscript 1/2] from which we extract an effective slip length of b ≈ 19 μm. The dimensionless effective slip length b[superscript +] = b/δ[subscript ν], where δ[subscript ν] is the viscous length scale, is the key parameter that governs the drag reduction and is shown to scale as b[[superscript +] ~ Re[superscript 1/2] in the limit of high Re. United States. Office of Naval Research (Contract 3002453814) 2015-01-13T20:07:31Z 2015-01-13T20:07:31Z 2015-01 2014-11 2015-01-06T23:00:04Z Article http://purl.org/eprint/type/JournalArticle 0031-9007 1079-7114 http://hdl.handle.net/1721.1/92834 Srinivasan, Siddarth, et al. "Sustainable Drag Reduction in Turbulent Taylor-Couette Flows by Depositing Sprayable Superhydrophobic Surfaces." Phys. Rev. Lett. 114 (January 2015), 014501. © 2015 American Physical Society https://orcid.org/0000-0002-3873-2472 https://orcid.org/0000-0003-4591-6090 https://orcid.org/0000-0001-8323-2779 https://orcid.org/0000-0003-1085-7692 en http://dx.doi.org/10.1103/PhysRevLett.114.014501 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. American Physical Society application/pdf American Physical Society American Physical Society |
| spellingShingle | Srinivasan, Siddarth Gilbert, Jonathan Brian Cohen, Robert E. McKinley, Gareth H. Kleingartner, Justin Alan Milne, Andrew James Barnabas Sustainable Drag Reduction in Turbulent Taylor-Couette Flows by Depositing Sprayable Superhydrophobic Surfaces |
| title | Sustainable Drag Reduction in Turbulent Taylor-Couette Flows by Depositing Sprayable Superhydrophobic Surfaces |
| title_full | Sustainable Drag Reduction in Turbulent Taylor-Couette Flows by Depositing Sprayable Superhydrophobic Surfaces |
| title_fullStr | Sustainable Drag Reduction in Turbulent Taylor-Couette Flows by Depositing Sprayable Superhydrophobic Surfaces |
| title_full_unstemmed | Sustainable Drag Reduction in Turbulent Taylor-Couette Flows by Depositing Sprayable Superhydrophobic Surfaces |
| title_short | Sustainable Drag Reduction in Turbulent Taylor-Couette Flows by Depositing Sprayable Superhydrophobic Surfaces |
| title_sort | sustainable drag reduction in turbulent taylor couette flows by depositing sprayable superhydrophobic surfaces |
| url | http://hdl.handle.net/1721.1/92834 https://orcid.org/0000-0002-3873-2472 https://orcid.org/0000-0003-4591-6090 https://orcid.org/0000-0001-8323-2779 https://orcid.org/0000-0003-1085-7692 |
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