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Sharp-interface limit of the Cahn–Hilliard model for moving contact lines

Published online by Cambridge University Press:  22 February 2010

PENGTAO YUE*
Affiliation:
Department of Mathematics, Virginia Polytechnic Institute and State University, Blacksburg, VA 24061-0123, USA
CHUNFENG ZHOU
Affiliation:
Department of Chemical and Biological Engineering, University of British Columbia, Vancouver, BC V6T 1Z3, Canada
JAMES J. FENG
Affiliation:
Department of Chemical and Biological Engineering, University of British Columbia, Vancouver, BC V6T 1Z3, Canada Department of Mathematics, University of British Columbia, Vancouver, BC V6T 1Z2, Canada
*
Email address for correspondence: ptyue@math.vt.edu

Abstract

Diffuse-interface models may be used to compute moving contact lines because the Cahn–Hilliard diffusion regularizes the singularity at the contact line. This paper investigates the basic questions underlying this approach. Through scaling arguments and numerical computations, we demonstrate that the Cahn–Hilliard model approaches a sharp-interface limit when the interfacial thickness is reduced below a threshold while other parameters are fixed. In this limit, the contact line has a diffusion length that is related to the slip length in sharp-interface models. Based on the numerical results, we propose a criterion for attaining the sharp-interface limit in computing moving contact lines.

Type
Papers
Copyright
Copyright © Cambridge University Press 2010

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References

REFERENCES

Blake, T. D. 2006 The physics of moving wetting lines. J. Colloid Interface Sci. 299, 113.CrossRefGoogle ScholarPubMed
Briant, A. J. & Yeomans, J. M. 2004 Lattice Boltzmann simulations of contact line motion. Part II. Binary fluids. Phys. Rev. E 69, 031603.CrossRefGoogle Scholar
Caginalp, G. & Chen, X. 1998 Convergence of the phase field model to its sharp interface limits. Eur. J. Appl. Math. 9, 417445.CrossRefGoogle Scholar
Cahn, J. W. 1977 Critical-point wetting. J. Chem. Phys. 66, 36673672.CrossRefGoogle Scholar
Cahn, J. W. & Hilliard, J. E. 1958 Free energy of a non-uniform system. Part I. interfacial free energy. J. Chem. Phys. 28, 258267.CrossRefGoogle Scholar
Chen, H.-Y., Jasnow, D. & Viñals, J. 2000 Interface and contact line motion in a two phase fluid under shear flow. Phys. Rev. Lett. 85, 16861689.CrossRefGoogle Scholar
Cox, R. G. 1986 The dynamics of the spreading of liquids on a solid surface. Part 1. Viscous flow. J. Fluid Mech. 168, 169194.CrossRefGoogle Scholar
Ding, H. & Spelt, P. D. M. 2007 Inertial effects in droplet spreading: a comparison between diffuse-interface and level-set simulations. J. Fluid Mech. 576, 287296.CrossRefGoogle Scholar
Dussan, E. B. V. 1979 On the spreading of liquids on solid surfaces: static and dynamic contact lines. Annu. Rev. Fluid Mech. 11, 371400.CrossRefGoogle Scholar
Fermigier, M. & Jenffer, P. 1991 An experimental investigation of the dynamic contact angle in liquid–liquid systems. J. Colloid Interface Sci. 146, 226241.CrossRefGoogle Scholar
Haley, P. J. & Miksis, M. J. 1991 The effect of the contact line on droplet spreading. J. Fluid Mech. 223, 5781.CrossRefGoogle Scholar
Hoffman, R. L. 1975 A study of the advancing interface. J. Colloid Interface Sci. 50, 228241.CrossRefGoogle Scholar
Huang, J. J., Shu, C. & Chew, Y. T. 2009 Mobility-dependent bifurcations in capillarity-driven two-phase fluid systems by using a lattice Boltzmann phase-field model. Intl J. Numer. Method Fluids 60, 203225.CrossRefGoogle Scholar
Huh, C. & Scriven, L. E. 1971 Hydrodynamic model of steady movement of a solid/liquid/fluid contact line. J. Colloid Interface Sci. 35, 85101.CrossRefGoogle Scholar
Jacqmin, D. 1999 Calculation of two-phase Navier–Stokes flows using phase-field modelling. J. Comput. Phys. 155, 96127.CrossRefGoogle Scholar
Jacqmin, D. 2000 Contact-line dynamics of a diffuse fluid interface. J. Fluid Mech. 402, 5788.CrossRefGoogle Scholar
Jacqmin, D. 2004 Onset of wetting failure in liquid–liquid systems. J. Fluid Mech. 517, 209228.CrossRefGoogle Scholar
Khatavkar, V. V., Anderson, P. D. & Meijer, H. E. H. 2006 On scaling of diffuse-interface models. Chem. Engng Sci. 61, 23642378.CrossRefGoogle Scholar
Khatavkar, V. V., Anderson, P. D. & Meijer, H. E. H. 2007 Capillary spreading of a droplet in the partially wetting regime using a diffuse-interface model. J. Fluid Mech. 572, 367387.CrossRefGoogle Scholar
Koplik, J., Banavar, J. R. & Willemsen, J. F. 1988 Molecular dynamics of Poiseuille flow and moving contact lines. Phys. Rev. Lett. 60, 12821285.CrossRefGoogle ScholarPubMed
Lowengrub, J. & Truskinovsky, L. 1998 Quasi-incompressible Cahn–Hilliard fluids and topological transitions. Proc. R. Soc. Lond. A 454, 26172654.CrossRefGoogle Scholar
Mazouchi, A., Gramlich, C. M. & Homsy, G. M. 2004 Time-dependent free surface Stokes flow with a moving contact line. Part I. Flow over plane surfaces. Phys. Fluids 16, 16471659.CrossRefGoogle Scholar
Pismen, L. M. 2002 Mesoscopic hydrodynamics of contact line motion. Colloids Surf. A 206, 1130.CrossRefGoogle Scholar
Qian, T., Wang, X.-P. & Sheng, P. 2003 Molecular scale contact line hydrodynamics of immiscible flows. Phys. Rev. E 68, 016306.CrossRefGoogle ScholarPubMed
Qian, T., Wang, X.-P. & Sheng, P. 2006 a Molecular hydrodynamics of the moving contact line in two-phase immiscible flows. Comm. Comput. Phys. 1, 152.Google Scholar
Qian, T., Wang, X.-P. & Sheng, P. 2006 b A variational approach to moving contact line hydrodynamics. J. Fluid Mech. 564, 333360.CrossRefGoogle Scholar
Renardy, M., Renardy, Y. & Li, J. 2001 Numerical simulation of moving contact line problems using a volume-of-fluid method. J. Comput. Phys. 171, 243263.CrossRefGoogle Scholar
Seppecher, P. 1996 Moving contact lines in the Cahn–Hilliard theory. Intl J. Engng Sci. 34, 977992.CrossRefGoogle Scholar
Sheng, P. & Zhou, M.-Y. 1992 Immiscible-fluid displacement: contact-line dynamics and the velocity-dependent capillary pressure. Phys. Rev. A 45, 56945708.CrossRefGoogle ScholarPubMed
Spelt, P. D. M. 2005 A level-set approach for simulations of flows with multiple moving contact lines with hysteresis. J. Comput. Phys. 207, 389404.CrossRefGoogle Scholar
Thompson, P. A. & Robbins, M. O. 1989 Simulations of contact-line motion: slip and the dynamic contact angle. Phys. Rev. Lett. 63, 766769.CrossRefGoogle ScholarPubMed
Villanueva, W. & Amberg, G. 2006 Some generic capillary-driven flows. Intl J. Multiphase Flow 32, 10721086.CrossRefGoogle Scholar
vander Waals, J. D. der Waals, J. D. 1892 The thermodynamic theory of capillarity under the hypothesis of a continuous variation of density. Verhandel Konink. Akad. Weten. Amsterdam (Sec. 1) 1, 156. Translation by J. S. Rowlingson, 1979, J. Stat. Phys. 20, 197–244.Google Scholar
Wang, X.-P. & Wang, Y.-G. 2007 The sharp interface limit of a phase field model for moving contact line problem. Methods Appl. Anal. 14, 287294.CrossRefGoogle Scholar
Yue, P., Feng, J. J., Liu, C. & Shen, J. 2004 A diffuse-interface method for simulating two-phase flows of complex fluids. J. Fluid Mech. 515, 293317.CrossRefGoogle Scholar
Yue, P., Zhou, C. & Feng, J. J. 2007 Spontaneous shrinkage of drops and mass conservation in phase-field simulations. J. Comput. Phys. 223, 19.CrossRefGoogle Scholar
Yue, P., Zhou, C., Feng, J. J., Ollivier-Gooch, C. F. & Hu, H. H. 2006 Phase-field simulations of interfacial dynamics in viscoelastic fluids using finite elements with adaptive meshing. J. Comput. Phys. 219, 4767.CrossRefGoogle Scholar
Zhou, M.-Y. & Sheng, P. 1990 Dynamics of immiscible-fluid displacement in a capillary tube. Phys. Rev. Lett. 64, 882885.CrossRefGoogle Scholar