Trapping of Water Drops by Line-Shaped Defects on Superhydrophobic Surfaces
2015 (English)In: Langmuir, ISSN 0743-7463, E-ISSN 1520-5827, Vol. 31, no 23, 6367-6374 p.Article in journal (Refereed) Published
We have investigated the effect of line-shaped topographical defects on the motion of water drops across superhydrophobic wax surfaces using a high-speed video camera. The defects are introduced onto the superhydrophobic wax surfaces by a scratching procedure. It is demonstrated that the motion of a drop interacting with the defect can be approximated by a damped harmonic oscillator. Whether a drop passes or gets trapped by the defect is determined by the incident speed and the properties of the oscillator, specifically by the damping ratio and a nondimensional forcing constant representing the effects of gravity and pinning forces. We also show that it is possible to predict a critical trapping speed as well as an exit speed in systems with negligible viscous dissipation using a simple work energy consideration.
Place, publisher, year, edition, pages
2015. Vol. 31, no 23, 6367-6374 p.
IdentifiersURN: urn:nbn:se:kth:diva-171142DOI: 10.1021/acs.langmuir.5b01174ISI: 000356755300012PubMedID: 26010934ScopusID: 2-s2.0-84935000794OAI: oai:DiVA.org:kth-171142DiVA: diva2:842443
QC 201507202015-07-202015-07-202015-07-20Bibliographically approved