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Contact line dynamics of a liquidmeniscusadvancing in a microchannelwithchemicalheterogeneitiesC. Wylock1, M. Pradas2, B. Haut1, P. Colinet1 and S. Kalliadasis21Université Libre de Bruxelles – Transfers, Interfaces and Processes2Imperial College London – Chemical Engineering Department International Conference on Multiscale Complex Fluid Flows and Interfacial Phenomena MULTIFLOW 2010 Brussels, Belgium
Goal • Gas-liquidmeniscusmoving in a "Hele-Shaw celllike " microchannel • Surface chemicallyheterogeneous spatial distribution of wettingproperties • 2 configurations • Effect of chemicalheterogeneities on meniscusdynamics ? 2D configuration 3D configuration
Modelling • Phase field approach • f represents the 2 phases • Interface at f=0
Modelling • Phase field approach • f represents the 2 phases • Interface at f=0 • Equilibrium given by Ginzburg-Landau model Free energy formulation Double-well potential Chemical potential
Modelling • Phase field approach • f represents the 2 phases • Interface at f=0 • Equilibrium given by Ginzburg-Landau model Free energy formulation Double-well potential Chemical potential
Modelling • Wetting boundary condition • Conserved dynamic equation Standard deviation s = disorder strength [1] with [1]Cahn, J. Chem. Phys. 66 (1977), 3667
Results and discussion • 2D configuration • Typical simulation result • Statistical analysis on several disorder realisations
Results and discussion • 2D configuration • Typical simulation result • Statistical analysis on several disorder realisations
Results and discussion • 2D configuration • Typical simulation result • Statistical analysis on several disorder realisations
Results and discussion • 2D configuration • Typical simulation result • Statistical analysis on several disorder realisations
Results and discussion • 2D configuration • Typical simulation result • Statistical analysis on several disorder realisations Chemical disorder contact angle hysteresis enhanced by disorder strength
Results and discussion • 3D configuration • Typical simulation results • Contact line dynamics: preliminaryanalysis • interface widthfollows fractal dynamics ( scale-invariant growth) • pinning-depinningeffects • avalanche dynamics induced by the chemicaldisorder Statisticalanalysis to perform for variousdisorder configurations
Conclusion and future plans • Phase field contact line dynamics in chemically heterogeneous microchannel • Chemical disorder induces • 2D: hysteresis of contact angle hysteresis “jump” function of disorder strength • 3D: kinetic roughening process of contact line motion, pinning-depinning effects • Future plans • Statistical analysis for 3D configuration: • Characterization of the scaling growth factors • Avalanche dynamics
Modelling • Boundary conditions for 2D configuration
Modelling • Boundary conditions for 3D configuration
Results and discussion • 2D configuration • Typical simulation result • Statistical analysis on several disorder realisations Chemical disorder contact angle hysteresis enhanced by disorder strength
Results and discussion • 3D configuration • Typical simulation results • Contact line dynamic: preliminary analysis • interface width growth follows fractal dynamic
Results and discussion • 3D configuration • Typical simulation results • Contact line dynamic: preliminary analysis • interface width growth follows fractal dynamic ( size-invariant scaling factors) • pinning-depinning effect s • avalanche dynamic Pinning site Avalanche site