Flows and mixing in channels with misaligned superhydrophobic walls

Tatiana V. Nizkaya, Evgeny S. Asmolov, Jiajia Zhou, Friederike Schmid, and Olga I. Vinogradova
Phys. Rev. E 91, 033020 – Published 30 March 2015

Abstract

Aligned superhydrophobic surfaces with the same texture orientation reduce drag in the channel and generate secondary flows transverse to the direction of the applied pressure gradient. Here we show that a transverse shear can be easily generated by using superhydrophobic channels with misaligned textured surfaces. We propose a general theoretical approach to quantify this transverse flow by introducing the concept of an effective shear tensor. To illustrate its use, we present approximate theoretical solutions and Dissipative Particle Dynamics simulations for striped superhydrophobic channels. Our results demonstrate that the transverse shear leads to complex flow patterns, which provide a new mechanism of a passive vertical mixing at the scale of a texture period. Depending on the value of Reynolds number two different scenarios occur. At relatively low Reynolds number the flow represents a transverse shear superimposed with two corotating vortices. For larger Reynolds number these vortices become isolated, by suppressing fluid transport in the transverse direction.

  • Figure
  • Figure
  • Figure
  • Figure
  • Figure
  • Figure
  • Figure
3 More
  • Received 23 September 2014

DOI:https://doi.org/10.1103/PhysRevE.91.033020

©2015 American Physical Society

Authors & Affiliations

Tatiana V. Nizkaya1,*, Evgeny S. Asmolov1,2,*, Jiajia Zhou3,*, Friederike Schmid3, and Olga I. Vinogradova1,4,5,†

  • 1A.N. Frumkin Institute of Physical Chemistry and Electrochemistry, Russian Academy of Science, 31 Leninsky Prospect, 119991 Moscow, Russia
  • 2Central Aero-Hydrodynamic Institute, 140180 Zhukovsky, Moscow region, Russia
  • 3Institut für Physik, Johannes Gutenberg-Universität Mainz, D55099 Mainz, Germany
  • 4Department of Physics, M.V. Lomonosov Moscow State University, 119991 Moscow, Russia
  • 5DWI-Leibniz Institute for Interactive Materials, RWTH Aachen, Forckenbeckstrasse 50, 52056 Aachen, Germany

  • *These three authors contributed equally to the work.
  • oivinograd@yahoo.com

Article Text (Subscription Required)

Click to Expand

References (Subscription Required)

Click to Expand
Issue

Vol. 91, Iss. 3 — March 2015

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 E

Log In

Cancel
×

Search


Article Lookup

Paste a citation or DOI

Enter a citation
×