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Transient flow of gravity-driven viscous films over substrates with rectangular topographical features

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Abstract

We study the transient, two-dimensional film flow over solid substrates with variable topography, a flow that has practical applications in microelectronics and microfluidics. The problem we address here is the advancing of a thin liquid film over square-shaped trenches with different depths and widths, under the influence of the gravitational force. We use the volume-of-fluid method to obtain completely different wetting patterns depending on the dimensions of the topography, the capillary and Reynolds numbers, and the contact angle. On one hand, we predict continuous coating, i.e., the formation of the Wenzel state, in which a thin liquid film covers the entire trench, while steady flow is established upstream and downstream this topographical feature. This is the desirable pattern, when perfect coating is sought, as in the manufacturing of microelectronic devices. Under different conditions, we predict that the film almost completely bypasses the trench, entrapping air inside it, i.e., forming the Cassie state. The coating quality is clearly poor in this case, but this pattern reduces the drag on the film, and therefore, it is desirable in the operation of super-hydrophobic surfaces for microfluidic applications. Between these two extreme configurations, we uncover a large variety of patterns, in which the film partially wets the trench forming an air inclusion all along its bottom or its upstream or downstream inner corners or the film may break up periodically. We produce comprehensive flow maps covering a wide range of relevant parameter values.

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References

  • Aksel N (2000) Influence of the capillarity on the creeping film flow down an inclined plane with an edge. Arch Appl Mech 70:81–90

    Article  MATH  Google Scholar 

  • Argyriadi K, Vlachogiannis M, Bontozoglou V (2006) Experimental study of inclined film flow along periodic corrugations: the effect of wall steepness. Phys Fluids 18(1):012102

    Article  Google Scholar 

  • Βico J, Quére D (2002) Self-propelling slugs. J Fluid Mech 467:101–127

    MATH  Google Scholar 

  • Bielarz C, Kalliadasis S (2003) Time-dependent free-surface thin film flows over topography. Phys Fluids 15:2512–2524

    Article  MathSciNet  MATH  Google Scholar 

  • Bontozoglou V, Serifi K (2008) Falling film flow along steep two-dimensional topography: the effect of inertia. Int J Multiph Flow 34:734–747

    Article  Google Scholar 

  • Bouwhuis W, van der Veen R, Tran T, Keij DL, Winkels KG, Peters IR, van der Meer D, Sun C, Snoeijer JH, Lohse D (2012) Maximal air bubble entrainment at liquid-drop impact. PRL 109:264501

    Article  Google Scholar 

  • Brackbill JU, Kothe DB, Zemach C (1992) A continuum method for modeling surface-tension. J Comput Phys 100:335–354

    Article  MathSciNet  MATH  Google Scholar 

  • Byun D, Kim J, Ko HS, Park HC (2008) Direct measurement of slip flows in superhydrophobic microchannels with transverse grooves. Phys Fluids 20:113601. doi:10.1063/1.3026609

    Article  MATH  Google Scholar 

  • Cao Z, Vlachogiannis M, Bontozoglou V (2013) Experimental evidence for a short-wave global mode in film flow along periodic corrugations. J Fluid Mech 718:304–320. doi:10.1017/jfm.2012.612

    Article  MATH  Google Scholar 

  • Chatzidai N, Giannousakis A, Dimakopoulos Y, Tsamopoulos J (2009) On the elliptic mesh generation in domains containing multiple inclusions and undergoing large deformations. J Comp Phys 228(6):1980–2011

    Article  MATH  Google Scholar 

  • Cottin-Bizonne CJL, Barrat L, Bocquet Charlaix E (2003) Low friction flows of liquid at nanopatterned interfaces. Nat Mater 2:237

    Article  Google Scholar 

  • Craster RV, Matar OK (2009) Dynamics and stability of thin liquid films. Rev Mod Phys 81(3):1131

    Article  Google Scholar 

  • Decré MMJ, Baret JC (2003) Gravity-driven flows of viscous liquids over two-dimensional topographies. J Fluid Mech 487:147–166

    Article  MATH  Google Scholar 

  • Dilip D, Boji MS, Govardhan RN (2015) Effect of absolute pressure on the flow through a textured hydrophobic microchannel. Microfluid Nanofluid. doi:10.1007/S10404-015-1655-4

    Google Scholar 

  • Dimakopoulos Y, Tsamopoulos J (2003) A quasi-elliptic transformation for moving boundary problems with large anisotropic deformations. J Comp Phys 192:494–522

    Article  MATH  Google Scholar 

  • Dussan VEB (1979) On the spreading of liquids on solid surfaces: static and dynamic contact angles. Annu Rev Fluid Mech 11:371

    Article  Google Scholar 

  • Fraggedakis D, Kouris Ch, Dimakopoulos Y, Tsamopoulos J (2015) Flow of two immiscible fluids in a periodically constricted tube: transitions to stratified, segmented, churn, spray or segregated flow. Phys Fluids 27:082102

    Article  Google Scholar 

  • Gao P, Feng JJ (2009) Enhanced slip on a patterned substrate due to depinning of contact line. Phys Fluids 21:102102

    Article  MATH  Google Scholar 

  • Gaskell PH, Jimack PK, Sellier M, Thompson HM, Wilson CT (2004) Gravity-driven flow of continuous thin liquid films on non-porous substrates with topography. J Fluid Mech 509:253–280

    Article  MathSciNet  MATH  Google Scholar 

  • Goodwin R, Homsy GM (1991) Viscous flow down a slope in the vicinity of a contact line. Phys Fluids A 3:515–528

    Article  MATH  Google Scholar 

  • Gopala VR, van Wachem B (2008) Volume of fluid for immiscible-fluid and free-surface flows Chem. Eng J 141:204–221

    Google Scholar 

  • Gramlich CM, Mazouchi A, Homsy GM (2004) Time-dependent free surface Stokes flow with a moving contact line. II. Flow over wedges and trenches. Phys Fluids 16:1660–1667

    Article  MathSciNet  MATH  Google Scholar 

  • Heining C, Bontozoglou V, Aksel N, Wierschem A (2009) Nonlinear resonance in viscous films on inclined wavy planes. Int J Multiph Flow 35(1):78–90

    Article  Google Scholar 

  • Hirt CW, Nichols BD (1981) Volume of fluid (VOF) method for the dynamics of the free boundaries. J Comput Phys 39:201–225

    Article  MATH  Google Scholar 

  • Huppert H (1982) Flow and instability of viscous current down a slope. Nature 300:427

    Article  Google Scholar 

  • Issa RI (1986) Solution of the implicitly discretized fluid flow equations by operator-splitting. J Comput Phys 62:40–65

    Article  MathSciNet  MATH  Google Scholar 

  • Kalliadasis S, Homsy GM (2001) Stability of free-surface thin film flows over topography. J Fluid Mech 448:387–410

    MathSciNet  MATH  Google Scholar 

  • Kalliadasis S, Bielarz C, Homsy GM (2000) Steady free surface thin film flows over topography. Phys Fluids 12:1889

    Article  MathSciNet  MATH  Google Scholar 

  • Kistler SF, Scriven LE (1984) Coating flow theory by finite element and asymptotic analysis of the Navier-Stokes system. Int J Numer Meth Fluids 4(3):207–229

    Article  MATH  Google Scholar 

  • Kouris Ch, Tsamopoulos J (2001a) Core-annular flow in a periodically constricted circular tube, I. Steady state, linear stability and energy analysis. J Fluid Mech 432:31–68

    MATH  Google Scholar 

  • Kouris Ch, Tsamopoulos J (2001b) Dynamics of axisymmetric core-annular flow in a straight tube: I. The more viscous fluid in the core, bamboo waves. Phys Fluids 13(4):841–858

    Article  MATH  Google Scholar 

  • Kusumaatmaja H, Pooley CM, Girardo S, Pisignano D, Yeomans JM (2008) Capillary filling in patterned channels. Phys Rev E 77:067301

    Article  Google Scholar 

  • Li J, Renardy Y, Renardy M (2000a) A numerical study of periodic disturbances on two-layer Couette flow. Phys Fluids 12(10):3056–3071

    Google Scholar 

  • Li J, Renardy Y, Renardy M (2000b) Numerical simulation of breakup of a viscous drop in simple shear flow through a volume-of fluid method. Phys Fluids 12(2):269–282

    Article  MATH  Google Scholar 

  • Lv P, Xue Y, Shi Y, Lin H, Duan H (2014) Metastable states and wetting transition of submerged superhydrophobic structures. PRL 112:196101

    Article  Google Scholar 

  • Malamataris N, Bontozoglou V (1999) Computer aided analysis of viscous film flow along an inclined wavy wall. J Comput Phys 154:372

    Article  MATH  Google Scholar 

  • Mazloomi A, Moosavi A (2013) Thin liquid film flow over substrates with two topographical features. Phys Rev E 87:022409

    Article  Google Scholar 

  • Mazloomi A, Moosavi A, Esmaili E (2013) Gravity-driven thin liquid films over topographical substrates Eur. Phys J E 36:58

    Google Scholar 

  • Mazouchi A, Homsy GM (2001) Free surface Stokes flow over topography. Phys Fluids 13(10):2751–2761

    Article  MATH  Google Scholar 

  • Mazouchi A, Gramlich CM, Homsy GM (2004) Time-dependent free surface Stokes flow with a moving contact line. I. Flow over plane surfaces. Phys Fluids 16:1647–1659

    Article  MathSciNet  MATH  Google Scholar 

  • OpenFOAM version 2.3.1, (2013). http://www.openfoam.org.

  • Pavlidis M, Dimakopoulos Y, Tsamopoulos J (2010) Steady viscoelastic film flow over 2D topography: I. The effect of viscoelastic properties under creeping flow. J NonNewton Fluid Mech 165:576–591

    Article  MATH  Google Scholar 

  • Richards J, Lenhoff A, Beris A (1994) Dynamic breakup of liquid-liquid jets. Phys Fluids A 6(8):2640–2655

    Article  MATH  Google Scholar 

  • Rothstein JP (2010) Slip on superhydrophobic surfaces. Ann Rev Fluid Mech 42:89–109

    Article  Google Scholar 

  • Ruiter JD, Oh JM, Ende DVD, Mugele F (2012) Dynamics of collapse of air films in drop impact. PRL 108:074505

    Article  Google Scholar 

  • Saprykin S, Koopmans RJ, Kalliadasis S (2007) Free-surface thin-film flows over topography: influence of inertia and viscoelasticity. J Fluid Mech 578:271–293

    Article  MathSciNet  MATH  Google Scholar 

  • Scardovelli R, Zaleski S (1999) Direct numerical simulation of free-surface and interfacial flow. Annu Rev Fluid Mech 31:567–603

    Article  MathSciNet  Google Scholar 

  • Scholle M, Haas A, Aksel N, Wilson MCT, Thompson HM, Gaskell PH (2008) Competing geometric and inertia effects on local flow structure in thick gravity-driven fluid films. Phys Fluids 20:123101

    Article  MATH  Google Scholar 

  • Sisoev GM, Matar OK, Lawrence CJ (2003) Axisymmetric wave regimes in viscous liquid film over a spinning disk. J Fluid Mech 495:385–411

    Article  MathSciNet  MATH  Google Scholar 

  • Spaid MA, Homsy GM (1996) Stability of Newtonian and viscoelastic dynamic contact lines. Phys Fluids 8:460–478

    Article  MathSciNet  MATH  Google Scholar 

  • Stillwagon LE, Larson RG (1990) Leveling of thin films over uneven substrates during spin coating. Phys Fluids 2(11):1937–1944

    Article  Google Scholar 

  • Teo CJ, Khoo BC (2010) Flow past superhydrophobic surfaces containing longitudinal grooves: effects of interface curvature. Microfluid Nanofluid 9:499–511

    Article  Google Scholar 

  • Veremieiev S, Thompson HM, Lee YC, Gaskell PH (2010) Inertial thin film flow on planar surfaces featuring topography. Comput Fluids 39:431–450

    Article  MATH  Google Scholar 

  • Vlachogiannis M, Bontozoglou V (2002) Experiments on laminar film flow along a periodic wall. J Fluid Mech 457:133–156

    MATH  Google Scholar 

  • Wardle KE, Weller HG (2013) Hybrid Multiphase CFD dolver for coupled dispersed/segregated flows in liquid-liquid extraction. Int J Chem Eng 2013:1–13, Art ID 128936. doi:10.1155/2013/128936

  • Wierschem A, Aksel N (2004) Influence of inertia on eddies created in films creeping over strongly undulated substrates. Phys Fluids 16(12):4566–4574

    Article  MATH  Google Scholar 

  • Yamada T, Hong C, Gregory OJ, Faghri M (2011) Experimental investigations of liquid flow in rib-patterned microchannels with different surface wettability. Microfluid Nanofluid 11:45–55

    Article  Google Scholar 

  • Yin X, Kumar S (2006) Flow visualization of the liquid-emptying process in scaled-up gravure grooves and cells. Chem Eng Sci 61:1146–1156

    Article  Google Scholar 

  • Yue P, Renardy Y (2013) Spontaneous penetration of a non-wetting drop into an exposed pore. Phys Fluids 25:052104

    Article  MATH  Google Scholar 

  • Zacharioudaki MCh, Kouris Y Dimakopoulos, Tsamopoulos J (2007) A direct comparison between volume and surface tracking methods with a boundary-fitted coordinate transformation and 3rd order upwinding. J Comput Phys 227(2):1428–1469

    Article  MathSciNet  MATH  Google Scholar 

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Acknowledgments

This work has been supported financially by the General Secretariat of Research and Technology of Greece through the program “Excellence” (Grant No. 1918, entitled “FilCoMicrA”) in the framework “Education and Lifelong Learning” co-funded by the European Social Fund and National Resources. We also acknowledge useful discussions with D. Fraggedakis and G. Karapetsas.

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Correspondence to J. Tsamopoulos.

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Lampropoulos, N.K., Dimakopoulos, Y. & Tsamopoulos, J. Transient flow of gravity-driven viscous films over substrates with rectangular topographical features. Microfluid Nanofluid 20, 51 (2016). https://doi.org/10.1007/s10404-016-1716-3

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