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Droplet dynamics on chemically heterogeneous substrates

Published online by Cambridge University Press:  16 November 2018

Nikos Savva*
Affiliation:
School of Mathematics, Cardiff University, Cardiff CF24 4AG, UK
Danny Groves
Affiliation:
School of Mathematics, Cardiff University, Cardiff CF24 4AG, UK
Serafim Kalliadasis
Affiliation:
Department of Chemical Engineering, Imperial College London, London SW7 2AZ, UK
*
Email address for correspondence: savvan@cardiff.ac.uk

Abstract

Slow droplet motion on chemically heterogeneous substrates is considered analytically and numerically. We adopt the long-wave approximation which yields a single partial differential equation for the droplet height in time and space. A matched asymptotic analysis in the limit of nearly circular contact lines and vanishingly small slip lengths yields a reduced model consisting of a set of ordinary differential equations for the evolution of the Fourier harmonics of the contact line. The analytical predictions are found, within the domain of their validity, to be in good agreement with the solutions to the governing partial differential equation. The limitations of the reduced model when the contact line undergoes stronger deformations are partially lifted by proposing a hybrid scheme which couples the results of the asymptotic analysis with the boundary integral method. This approach improves the agreement with the governing partial differential equation, but at a computational cost which is significantly lower compared to that required for the full problem.

Type
JFM Papers
Copyright
© 2018 Cambridge University Press 

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References

Baltensperger, R., Berrut, J.-P. & Noel, B. 1999 Exponential convergence of a linear rational interpolant between transformed Chebyshev points. Maths Comput. 68 (227), 11091121.Google Scholar
Benilov, E. S. 2011 Thin three-dimensional drops on a slowly oscillating substrate. Phys. Rev. E 84 (6), 066301.Google Scholar
Benilov, E. S. & Benilov, M. S. 2015 A thin drop sliding down an inclined plate. J. Fluid Mech. 773, 75102.Google Scholar
Benilov, E. S. & Cummins, C. P. 2013 Thick drops on a slowly oscillating substrate. Phys. Rev. E 88 (2), 023013.Google Scholar
Bliznyuk, O., Vereshchagina, E., Kooij, E. S. & Poelsema, B. 2009 Scaling of anisotropic droplet shapes on chemically stripe-patterned surfaces. Phys. Rev. E 79 (4), 041601.Google Scholar
Bonn, D., Eggers, J., Indekeu, J., Meunier, J. & Rolley, E. 2009 Wetting and spreading. Rev. Mod. Phys. 81 (2), 739805.Google Scholar
Brinkmann, M. & Lipowsky, R. 2002 Wetting morphologies on substrates with striped surface domains. J. Appl. Phys. 92 (8), 42964306.Google Scholar
Brochard, F. 1989 Motions of droplets on solid surfaces induced by chemical or thermal gradients. Langmuir 5 (2), 432438.Google Scholar
Cassie, A. B. D. 1948 Contact angles. Discuss. Faraday Soc. 3, 1116.Google Scholar
Cassie, A. B. D. & Baxter, S. 1944 Wettability of porous surfaces. Trans. Faraday Soc. 40, 546551.Google Scholar
Cavalli, A., Musterd, M. & Mugele, F. 2015 Numerical investigation of dynamic effects for sliding drops on wetting defects. Phys. Rev. E 91 (2), 023013.Google Scholar
Chaudhury, M. K. & Whitesides, G. M. 1992 How to make water run uphill. Science 256 (5063), 15391541.Google Scholar
Chen, H., Su, Y. & Shizgal, B. D. 2000 A direct spectral collocation Poisson solver in polar and cylindrical coordinates. J. Comput. Phys. 160 (2), 453469.Google Scholar
Cubaud, T. & Fermigier, M. 2001 Faceted drops on heterogeneous surfaces. Europhys. Lett. 55 (2), 239245.Google Scholar
Cubaud, T. & Fermigier, M. 2004 Advancing contact lines on chemically patterned surfaces. J. Colloid Interface Sci. 269 (1), 171177.Google Scholar
Damle, V. G. & Rykaczewski, K. 2017 Nano-striped chemically anisotropic surfaces have near isotropic wettability. Appl. Phys. Lett. 110 (17), 171603.Google Scholar
Darhuber, A. A., Troian, S. M. & Reisner, W. W. 2001 Dynamics of capillary spreading along hydrophilic microstripes. Phys. Rev. E 64 (3), 031603.Google Scholar
Davis, P. J. & Rabinowitz, P. 1984 Methods of Numerical Integration, 2nd edn. Academic Press.Google Scholar
Diez, J. A., Kondic, L. & Bertozzi, A. 2000 Global models for moving contact lines. Phys. Rev. E 63 (1), 011208.Google Scholar
Dupuis, A. & Yeomans, J. M. 2004 Lattice Boltzmann modelling of droplets on chemically heterogeneous surfaces. Future Gener. Comput. Syst. 20 (6), 9931001.Google Scholar
Eggers, J. 2004 Toward a description of contact line motion at higher capillary numbers. Phys. Fluids 16 (9), 34913494.Google Scholar
Eggers, J. 2005 Contact line motion for partially wetting fluids. Phys. Rev. E 72 (6), 061605.Google Scholar
Ghosh, A., Beaini, S., Zhang, B. J., Ganguly, R. & Megaridis, C. M. 2014 Enhancing dropwise condensation through bioinspired wettability patterning. Langmuir 30 (43), 1310313115.Google Scholar
Glasner, K. B. 2005 A boundary integral formulation of quasi-steady fluid wetting. J. Comput. Phys. 207 (2), 529541.Google Scholar
Gottlieb, D. & Orszag, S. A. 1987 Numerical Analysis of Spectral Methods: Theory and Applications. Society for Industrial and Applied Mathematics.Google Scholar
Greenspan, H. P. 1978 On the motion of a small viscous droplet that wets a surface. J. Fluid Mech. 84 (1), 125143.Google Scholar
Greenspan, H. P. & McCay, B. M. 1981 On the wetting of a surface by a very viscous fluid. Stud. Appl. Maths 64 (2), 94112.Google Scholar
Haley, P. J. & Miksis, M. J. 1991 The effect of the contact line on droplet spreading. J. Fluid Mech. 223, 5781.Google Scholar
Hesthaven, J. S., Gottlieb, S. & Gottlieb, D. 2007 Spectral Methods for Time-Dependent Problems. Cambridge University Press.Google Scholar
Hocking, L. M. 1983 The spreading of a thin drop by gravity and capillarity. Q. J. Mech. Appl. Maths 36 (1), 5569.Google Scholar
Hocking, L. M. 1992 Rival contact-angle models and the spreading of drops. J. Fluid Mech. 239, 671781.Google Scholar
Huang, W. & Sloan, D. M. 1993 Pole condition for singular problems: The pseudospectral approximation. J. Comput. Phys. 107 (2), 254261.Google Scholar
Huh, C. & Scriven, L. E. 1971 Hydrodynamic model of steady movement of a solid/liquid/fluid contact line. J. Colloid Interface Sci. 35 (1), 85101.Google Scholar
Ichimura, K., Sang-Keun, O. & Nakagawa, M. 2000 Light-driven motion of liquids on a photoresponsive surface. Science 288 (5471), 16241626.Google Scholar
Ito, Y., Heydari, M., Hashimoto, A., Konno, T., Hirasawa, A., Hori, S., Kurita, K. & Nakajima, A. 2007 The movement of a water droplet on a gradient surface prepared by photodegradation. Langmuir 23 (4), 18451850.Google Scholar
Jansen, H. P., Sotthewes, K., Ganser, C., Teichert, C., Zandvliet, H. J. W. & Kooij, E. S. 2012 Tuning kinetics to control droplet shapes on chemically striped patterned surfaces. Langmuir 28 (37), 1313713142.Google Scholar
Jansen, H. P., Sotthewes, K., Ganser, C., Zandvliet, H. J. W., Teichert, C. & Kooij, E. S. 2014 Shape of picoliter droplets on chemically striped patterned substrates. Langmuir 30 (39), 1157411581.Google Scholar
Joanny, J. F. & de Gennes, P. G. 1984 A model for contact angle hysteresis. J. Chem. Phys. 81 (1), 552562.Google Scholar
King, J. R. 2001 Thin-film flows and high-order degenerate parabolic equations.. In IUTAM Symposium on Free Surface Flows (ed. King, A. C. & Shikhmurzaev, Y. D.), pp. 718. Springer.Google Scholar
Kress, R. 1989 Linear Integral Equations. Springer.Google Scholar
Kusumaatmaja, H. & Yeomans, J. M. 2007 Modeling contact angle hysteresis on chemically patterned and superhydrophobic surfaces. Langmuir 23 (11), 60196032.Google Scholar
Lacey, A. A. 1982 The motion with slip of a thin viscous droplet over a solid surface. Stud. Appl. Maths 67 (3), 217230.Google Scholar
Le Doussal, P. & Wiese, K. J. 2010 Elasticity of a contact-line and avalanche-size distribution at depinning. Phys. Rev.  E 82 (1), 011108.Google Scholar
Meron, E. 1992 Pattern formation in excitable media. Phys. Rep. 218, 166.Google Scholar
Morita, M., Koga, T., Otsuka, H. & Takahara, A. 2005 Macroscopic-wetting anisotropy on the line-patterned surface of fluoroalkylsilane monolayers. Langmuir 21 (3), 911918.Google Scholar
Moumen, N., Subramanian, R. S. & McLaughlin, J. B. 2006 Experiments on the motion of drops on a horizontal solid surface due to a wettability gradient. Langmuir 22 (6), 26822690.Google Scholar
Oliver, J. M., Whiteley, J. P., Saxton, M. A., Vella, D., Zubkov, V. S. & King, J. R. 2015 On contact-line dynamics with mass transfer. Eur. J. Appl. Maths 26, 149.Google Scholar
Pismen, L. M. 2006 Perturbation theory for traveling droplets. Phys. Rev. E 74 (4), 041605.Google Scholar
Ruckenstein, E & Dunn, C. S. 1977 Slip velocity during wetting of solids. J. Colloid Interface Sci. 59 (1), 135138.Google Scholar
Savva, N. & Kalliadasis, S. 2009 Two-dimensional droplet spreading over topographical substrates. Phys. Fluids 21 (9), 092102.Google Scholar
Savva, N. & Kalliadasis, S. 2011 Dynamics of moving contact lines: A comparison between slip and precursor film models. Europhys. Lett. 94 (6), 64004.Google Scholar
Savva, N. & Kalliadasis, S. 2012 Influence of gravity on the spreading of two-dimensional droplets over topographical substrates. J. Engng Maths 73 (1), 316.Google Scholar
Savva, N. & Kalliadasis, S. 2013 Droplet motion on inclined heterogeneous substrates. J. Fluid Mech. 725, 462491.Google Scholar
Savva, N. & Kalliadasis, S. 2014 Low-frequency vibrations of two-dimensional droplets on heterogeneous substrates. J. Fluid Mech. 754, 515549.Google Scholar
Savva, N., Rednikov, A. & Colinet, P. 2017 Asymptotic analysis of the evaporation dynamics of partially wetting droplets. J. Fluid Mech. 824, 574623.Google Scholar
Saxton, M. A., Whiteley, J. P., Vella, D. & Oliver, J. M. 2016 On thin evaporating drops: When is the d 2 -law valid? J. Fluid Mech. 792, 134167.Google Scholar
Sbragaglia, M., Biferale, L., Amati, G., Varagnolo, S., Ferraro, D., Mistura, G. & Pierno, M. 2014 Sliding drops across alternating hydrophobic and hydrophilic stripes. Phys. Rev. E 89 (1), 012406.Google Scholar
Schwartz, L. W. 1998 Hysteretic effects in droplet motions on heterogeneous substrates: Direct numerical simulation. Langmuir 14 (12), 34403453.Google Scholar
Schwartz, L. W. & Eley, R. R. 1998 Simulation of droplet motion on low-energy and heterogeneous surfaces. J. Colloid Interface Sci. 202 (1), 173188.Google Scholar
Sibley, D. N., Nold, A. & Kalliadasis, S. 2015a The asymptotics of the moving contact line: Cracking an old nut. J. Fluid Mech. 764, 445462.Google Scholar
Sibley, D. N., Nold, A., Savva, N. & Kalliadasis, S. 2013 On the moving contact line singularity: Asymptotics of a diffuse-interface model. Eur. Phys. J. E 36 (3), 26.Google Scholar
Sibley, D. N., Nold, A., Savva, N. & Kalliadasis, S. 2015b A comparison of slip, disjoining pressure, and interface formation models for contact line motion through asymptotic analysis of thin two-dimensional droplet spreading. J. Engng Maths 94 (1), 1941.Google Scholar
Sibley, D. N., Savva, N. & Kalliadasis, S. 2012 Slip or not slip? A methodical examination of the interface formation model using two-dimensional droplet spreading on a horizontal planar substrate as a prototype system. Phys. Fluids 24 (8), 082105.Google Scholar
Snoeijer, J. H. & Andreotti, B. 2013 Moving contact lines: Scales, regimes, and dynamical transitions. Annu. Rev. Fluid Mech. 45 (1), 269292.Google Scholar
Subramanian, R. S., Moumen, N. & McLaughlin, J. B. 2005 Motion of a drop on a solid surface due to a wettability gradient. Langmuir 21 (25), 1184411849.Google Scholar
Sui, Y., Ding, H. & Spelt, P. D. M. 2014 Numerical simulations of flows with moving contact lines. Annu. Rev. Fluid Mech. 46 (1), 97119.Google Scholar
Suzuki, S., Nakajima, A., Tanaka, K., Sakai, M., Hashimoto, A., Yoshida, N., Kameshima, Y. & Okada, K. 2008 Sliding behavior of water droplets on line-patterned hydrophobic surfaces. Appl. Surf. Sci. 254 (6), 17971805.Google Scholar
Tanguy, A. & Vettorel, T. 2004 From weak to strong pinning. Part I. A finite size study. Eur. Phys. J. B 38 (1), 7182.Google Scholar
Teh, S.-Y., Lin, R., Hung, L.-H. & Lee, A. P. 2008 Droplet microfluidics. Lab on a Chip 8 (2), 198220.Google Scholar
Trefethen, L. N. 2000 Spectral Methods in MATLAB. SIAM.Google Scholar
Varagnolo, S., Schiocchet, V., Ferraro, D., Pierno, M., Mistura, G., Sbragaglia, M., Gupta, A. & Amati, G. 2014 Tuning drop motion by chemical patterning of surfaces. Langmuir 30 (9), 24012409.Google Scholar
Vellingiri, R., Savva, N. & Kalliadasis, S. 2011 Droplet spreading on chemically heterogeneous substrates. Phys. Rev. E 84 (3), 036305.Google Scholar
Wang, H., Huybrechs, D. & Vandewalle, S. 2014 Explicit barycentric weights for polynomial interpolation in the roots or extrema of classical orthogonal polynomials. Maths Comput. 83 (290), 28932914.Google Scholar
Xu, F. & Jensen, O. E. 2016 Drop spreading with random viscosity. Proc. R. Soc. Lond. A 472 (2194), 20160270.Google Scholar
Young, G. W. 1994 Mathematical description of viscous free surface flows. In Free Boundaries in Viscous Flows (ed. Brown, R. A. & Davis, S. H.), pp. 127. Springer.Google Scholar