Modeling the Maximum Spreading of Liquid Droplets Impacting Wetting and Nonwetting Surfaces

• DOI: 10.1021/acs.langmuir.5b04557
• Publication Date: 2016-01-08T10:18:42Z
• Authors: Jae Bong Lee; Dominique Derome; Robert Guyer; Jan Carmeliet
• Keywords: Wetting transition

Droplet impact has been imaged on different rigid, smooth, and rough substrates for three liquids with viscosity surface tension, special attention to the lower velocity range. Of all studied parameters, only tension viscosity, thus liquid properties, clearly play a role in terms of attained maximum spreading ratio impacting droplet. Surface roughness type (steel, aluminum, parafilm) slightly affect dynamic wettability at low velocity. The contact angle identified properly characterize this process, especially where wetting plays an important role. is found be generally higher than equilibrium angle, showing that statically surfaces can become less or even nonwetting under droplet impact. An improved energy balance model proposed based correct analytical modeling time spreading, which determines viscous dissipation. Experiments show decreases depending liquid, scaling diameter proposed. A second improvement use instead quasi-static angles, describe process This showed good agreement compared experiments versus liquids, better prediction other models literature. In particular, according We(1/2) invalid velocities, since curves bend over ratios due process.