Contact line stability of ridges and drops
Abstract
Within the framework of a semi-microscopic interface displacement model in the small slope approximation we analyze the linear stability of sessile ridges and drops of a non-volatile liquid on a homogeneous, partially wet substrate, for both signs and arbitrary amplitudes of the three-phase contact line tension. Focusing on perturbations which correspond to deformations of the three-phase contact line, we find that drops are generally stable while ridges are subject only to the long-wavelength Rayleigh-Plateau instability leading to a breakup into droplets, in contrast to the predictions of capillary models which take line tension into account. We argue that the short-wavelength instabilities predicted within the framework of the latter macroscopic capillary theory occur outside its range of validity and thus are spurious.
- Publication:
-
EPL (Europhysics Letters)
- Pub Date:
- December 2007
- DOI:
- 10.1209/0295-5075/80/66002
- arXiv:
- arXiv:0707.3735
- Bibcode:
- 2007EL.....8066002M
- Keywords:
-
- Condensed Matter - Soft Condensed Matter
- E-Print:
- 6 pages, 1 figure