Contact angle hysteresis in a microchannel: Statics

Metin Hatipogullari, Christophe Wylock, Marc Pradas, Serafim Kalliadasis, and Pierre Colinet
Phys. Rev. Fluids 4, 044008 – Published 30 April 2019

Abstract

We study contact angle hysteresis in a chemically heterogeneous microchannel by tracking static meniscus configurations in the microchannel upon varying the volume of liquid. We first construct a graphical force balance similar to a previous approach by Joanny and de Gennes for this system, though here with a straight contact line. It is shown that hysteresis is induced by wettability gradients above a finite threshold value. This is also visualized in a phase-plane plot enabling to easily predict stick-slip events of the contact line and the occurrence of hysteresis. Above the threshold and for nonoverlapping Gaussian defects, we find good agreement with the expressions by Joanny and de Gennes for the hysteresis amplitude induced by a dilute system of defects. In particular, the hysteresis amplitude is found to be proportional to the square of the defect force and to the defect concentration. For a model sinusoidal heterogeneity, decreasing the ratio between the heterogeneity wavelength and the microchannel gap size brings the system from a subthreshold regime, to a stick-slip dominated regime, and finally to a regime with a quasiconstant advancing and receding angle. In the latter case, the hysteresis amplitude is found to be proportional to the defect force. We also consider an unusual heterogeneity for which the gradients of increasing and decreasing wettability are different. In such a situation breaking the left/right symmetry, whether or not hysteresis is observed will depend on the side the liquid enters the microchannel.

  • Figure
  • Figure
  • Figure
  • Figure
  • Figure
  • Figure
  • Figure
7 More
  • Received 2 March 2018

DOI:https://doi.org/10.1103/PhysRevFluids.4.044008

©2019 American Physical Society

Physics Subject Headings (PhySH)

Fluid Dynamics

Authors & Affiliations

Metin Hatipogullari* and Christophe Wylock

  • TIPs (Transfers, Interfaces, and Processes), Université Libre de Bruxelles C. P. 165/67, Av. F. D. Roosevelt 50, B-1050 Brussels, Belgium

Marc Pradas

  • School of Mathematics and Statistics, The Open University, Milton Keynes MK7 6AA, United Kingdom

Serafim Kalliadasis

  • Department of Chemical Engineering, Imperial College London, London, SW7 2AZ, United Kingdom

Pierre Colinet

  • TIPs (Transfers, Interfaces, and Processes), Université Libre de Bruxelles C. P. 165/67, Av. F. D. Roosevelt 50, B-1050 Brussels, Belgium

  • *metin.hatipogullari@ulb.ac.be

Article Text (Subscription Required)

Click to Expand

References (Subscription Required)

Click to Expand
Issue

Vol. 4, Iss. 4 — April 2019

Reuse & Permissions
Access Options
Author publication services for translation and copyediting assistance advertisement

Authorization Required


×
×

Images

×

Sign up to receive regular email alerts from Physical Review Fluids

Log In

Cancel
×

Search


Article Lookup

Paste a citation or DOI

Enter a citation
×