Short-time dynamics of partial wetting.
When a liquid drop contacts a wettable surface, the liquid spreads over the solid to minimize the total surface energy. The first moments of spreading tend to be rapid. For example, a millimeter-sized water droplet will wet an area having the same diameter as the drop within a millisecond. For perfectly wetting systems, this spreading is inertially dominated. Here we identify that even in the presence of a contact line, the initial wetting is dominated by inertia rather than viscosity. We find that the spreading radius follows a power-law scaling in time where the exponent depends on the equilibrium contact angle. We propose a model, consistent with the experimental results, in which the surface spreading is regulated by the generation of capillary waves.
Bird
James C
JC
School of Engineering and Applied Sciences, Harvard University, Cambridge, MA 02138, USA.
Mandre
Shreyas
S
Stone
Howard A
HA
D005990:Glycerol / Q000737:chemistry; D008956:Models, Chemical; D012825:Silicon / Q000737:chemistry; D014867:Water / Q000737:chemistry; D017155:Wettability
D014867:Water; D005990:Glycerol; D012825:Silicon