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arXiv · 1209.6150

Short time dynamics of viscous drop spreading

Antonin Eddi·Koen G. Winkels·Jacco H. Snoeijer
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Abstract

Liquid drops start spreading directly after coming into contact with a solid sub- strate. Although this phenomenon involves a three-phase contact line, the spread- ing motion can be very fast. We experimentally study the initial spreading dy- namics, characterized by the radius of the wetted area, for viscous drops. Using high-speed imaging with synchronized bottom and side views gives access to 6 decades of time resolution. We show that short time spreading does not exhibit a pure power-law growth. Instead, we find a spreading velocity that decreases logarithmically in time, with a dynamics identical to that of coalescing viscous drops. Remarkably, the contact line dissipation and wetting effects turn out to be unimportant during the initial stages of drop spreading.

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Antonin Eddi, Koen G. Winkels, Jacco H. Snoeijer. 2012-09-27. Short time dynamics of viscous drop spreading. https://doi.org/10.1063/1.4788693

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