Droplet on a conical fiber
Abstract
We study experimentally the behavior of a drop deposited on a conical fiber. The gradient of radius of the fiber we used is less than 1%, however, it is shown that for wetting liquids, such a drop spontaneously moves towards the region of lower curvature (i.e. toward the large radius of the fiber). The driving force is measured and shown to be a gradient of Laplace pressure. Then we characterize the dynamics of these self-propelling drops and found that the speed of the drop is proportionnal to the driving force and extremely sensitive toward the radius of the fiber. We interpret this data considering that the dissipation occurs in the bulk rather than in the vicinity of the contact line of the drop (which would have provided a non-linear dependency between the speed of the drop and the driving force). We conclude by discussing the efficiency of this device for drying a solid initially coated with a liquid film.
- Publication:
-
APS Division of Fluid Dynamics Meeting Abstracts
- Pub Date:
- November 2003
- Bibcode:
- 2003APS..DFD.MF005L