https://doi.org/10.1140/epje/i2016-16026-5
Regular Article
Mathematical modeling of pattern formation caused by drying of colloidal film under a mask
1
Astrakhan State University, Astrakhan, Russia
2
Rostov State University of Economics, Rostov on Don, Russia
* e-mail: tarasevich@asu.edu.ru
Received:
28
May
2015
Accepted:
17
September
2015
Published online:
26
February
2016
In our model, we simulate an experiment (D.J. Harris, H. Hu, J.C. Conrad, J.A. Lewis, Patterning colloidal films via evaporative lithography, Phys. Rev. Lett. 98, 148301 (2007)). A thin colloidal sessile droplet is allowed to dry out on a horizontal hydrophilic surface. A mask just above the droplet predominantly allows evaporation from the droplet free surface directly beneath the holes in the mask. We consider one special case, when the holes in the mask are arranged so that the system has rotational symmetry of order m . We use a speculative evaporative flux to mimic the real system. Advection, diffusion, and sedimentation are taken into account. FlexPDE is utilized to solve an advection-diffusion equation using the finite element method. The simulation demonstrates that the colloidal particles accumulate below the holes as the solvent evaporates. Diffusion can reduce this accumulation.
Key words: Topical Issue: Wetting and Drying: Physics and Pattern Formation
© EDP Sciences, SIF, Springer-Verlag Berlin Heidelberg, 2016