Abstract
In this study, pressure drops on liquid-infused superhydrophobic surfaces were measured through a microchannel. A number of different superhydrophobic surfaces were prepared and tested. These surfaces included several PDMS surfaces containing precisely patterned microposts and microridges as well as a number of PTFE surfaces with random surface roughness created by sanding the PTFE with different sandpapers. Silicone oil was selected as the lubricant fluid and infused into the microstructures of the superhydrophobic surfaces. Several aqueous glycerin solutions with different viscosities were used as working fluids so that the viscosity ratio between the lubricant and the working fluid could be varied. The lubricant layer trapped within the precisely patterned superhydrophobic PDMS surfaces was found to be easily depleted over a short period of time even in limit of low flow rates and capillary numbers. On the other hand, the randomly rough superhydrophobic PTFE surfaces tested were found to maintain the layer of lubricant oil even at moderately high capillary numbers resulting in drag reduction that was found to increase with increasing viscosity ratio. The pressure drops on the liquid-infused PTFE surfaces were measured over time to determine the longevity of the lubricant layer. The pressure drops for the randomly rough PTFE surfaces were found to initially diminish with time before reaching a short-time plateau which is equivalent to maximum drag reduction. This minimum pressure drop was maintained for at least three hours in all cases regardless of feature size. However, as the depletion of the oil from the lubricant layer was initiated, the pressure drop was observed to grow slowly before reaching a second long-time asymptote which was equivalent to a Wenzel state.
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Barthlott W, Neinhuis C (1997) Purity of the sacred lotus, or escape from contamination in biological surfaces. Planta 202:1–8
Bocquet L, Lauga E (2013) A smooth future? Nat Mater 10:334–337
Cao L, Jones AK, Sikka VK, Wu J, Gao D (2009) Anti-icing superhydrophobic coatings. Langmuir 25:12444–12448
Daniello R, Waterhouse NE, Rothstein JP (2009) Turbulent drag reduction using superhydrophobic surfaces. Phys Fluids 21:085103
Epstein AK, Wong T-S, Belisle RA, Boggs EM, Aizenberg J (2012) Liquid-infused structured surfaces with exceptional anti-biofouling performance. Proc Natl Acad Sci 109:13182–13187
Farhadi S, Farzaneh M, Kulinich SA (2011) Anti-icing performance of superhydrophobic surfaces. Appl Surf Sci 257:6264–6269
Furstner R, Barthlott W (2005) Wetting and self-cleaning properties of artificial superhydrophobic surfaces. Langmuir 21:956–961
Genzer J, Efimenko K (2006) Recent developments in superhydrophobic surfaces and their relevance to marine fouling: a review. Biofouling J Bioadhesion Biofilm Res 22:339–360
Jacobi I, Wexler JS, Samaha MA et al (2015a) Stratified thin-film flow in a rheometer. Phys Fluids 27:052102
Jacobi I, Wexler JS, Stone HA (2015b) Overflow cascades in liquid-infused substrates. Phys Fluids 27:082101
Kim P, Wong T-S, Alvarenga J, Kreder MJ, Adorno-Martinez WE, Aizenberg J (2012) Liquid-infused nanostructured surfaces with extreme anti-ice and anti-frost performance. ACS Nano 6:6569–6577
Kim J-H, Kavehpour HP, Rothstein JP (2015) Dynamic contact angle measurements on superhydrophobic surfaces. Phys Fluids 27:032107
Lafuma A, Quere D (2011) Slippery pre-suffused surfaces. Europhys Lett 96:56001
Lauga E, Stone HA (2003) Effective slip in pressure-driven stokes flow. J Fluid Mech 489:55–77
Li X-M, Reinhoudt D, Crego-Calama M (2007) What do we need for a superhydrophobic surface? A review on the recent progress in the preparation of superhydrophobic surfaces. Chem Soc Rev 36:1350–1368
McHale G, Shirtcliffe NJ, Evans CR, Newton MI (2009) Terminal velocity and drag reduction measurements on superhydrophobic spheres. App Phys Lett 94:064104
Milosevic IN, Longmire EK (2002) Pinch-off modes and satellite formation in liquid/liquid jet systems. Int J Multiph Flow 28:1853–1869
Mulligan MK, Rothstein JP (2011) The effect of confinement-induced shear on drop deformation and breakup in microfluidic extensional flows. Phys Fluids 23:022004
Nilsson M, Daniello R, Rothstein JP (2010) A novel and inexpensive technique for creating superhydrophobic surfaces using Teflon and sandpaper. J Phys D Appl Phys 43:045301
Ou J, Rothstein JP (2005) Direct velocity measurements of the flow past drag-reducing ultrahydrophobic surfaces. Phys Fluids 17:103606
Ou J, Perot JB, Rothstein JP (2004) Laminar drag reduction in microchannels using ultrahydrophobic surfaces. Phys Fluids 16:4635–4660
Quere D (2008) Wetting and roughness. Annu Rev Mater Res 38:71–99
Rothstein JP (2010) Slip on superhydrophobic surfaces. Annu Rev Fluid Mech 42:89–109
Smith JD, Dhiman R, Anand S et al (2013) Droplet mobility on lubricant-impregnated surfaces. Soft Matter 9:1772–1780
Solomon BR, Khalil KS, Varanasi KK (2014) Drag reduction using lubricant-impregnated surfaces in viscous laminar flow. Langmuir 30:10970–10976
Song D, Daniello R, Rothstein JP (2014) Drag reduction using superhydrophobic sanded Teflon surfaces. Exp Fluids 55:1783
Srinivasan S, Choi W, Park K-C, Chhatre SS, Cohen RE, McKinley GH (2013) Drag reduction for viscous laminar flow on spray-coated non-wetting surfaces. Soft Matter 9:5691–5702
Subramanyam SB, Rykaczewski K, Varanasi KK (2013) Ice adhesion on lubricant-impregnated textured surfaces. Langmuir 29:13414–13418
Truesdell R, Mammoli A, Vorobieff P, van Swol P, Brinker CJ (2006) Drag reduction on a patterned superhydrophobic surface. Phys Rev Lett 97:044504
Wexler JS, Grosskopf A, Chow M, Fan Y, Jacobi I, Stone HA (2015a) Robust liquid-infused surfaces through patterned wettability. Soft Matter 11:5023–5029
Wexler JS, Jacobi I, Stone HA (2015b) Shear-driven failure of liquid-infused surfaces. Phys Rev Lett 114:168301
Whitesides G, Stroock AD (2001) Flexible methods for microfluidics. Phys Today 54:42–48
Wong T-S, Kang SH, Tang SKY et al (2011) Bioinspired self-repairing slippery surfaces with pressure-stable omniphoicity. Nature 477:443–447
Yan YY, Gao N, Barthlott W (2011) Mimicking natural superhydrophobic surfaces and grasping the wetting process: a review on recent progress in preparing superhydrophobic surfaces. Adv Colloid Interface Sci 169:80–105
Ybert C, Barentin C, Cottin-Bizonne C, Joseph P, Bocquet L (2007) Achieving large slip with superhydrophobic surfaces: scaling laws for generic geometries. Phys Fluids 19:123601
Zhang H, Lamb R, Lewis J (2005) Engineering nanoscale roughness on hydrophobic surface-preliminary assessment of fouling behavior. Sci Technol Adv Mater 6:236–239
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This research was supported by the National Science Foundation under Grant CBET-1334962.
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Kim, JH., Rothstein, J.P. Delayed lubricant depletion on liquid-infused randomly rough surfaces. Exp Fluids 57, 81 (2016). https://doi.org/10.1007/s00348-016-2171-3
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DOI: https://doi.org/10.1007/s00348-016-2171-3