Dresden 2020 – wissenschaftliches Programm
Die DPG-Frühjahrstagung in Dresden musste abgesagt werden! Lesen Sie mehr ...
CPP 106.3: Vortrag
Freitag, 20. März 2020, 10:15–10:30, ZEU 260
Formation of a thin film during drop merging leads to fingering instability — •Peyman Rostami1,2 and Günter Auernhammer1,2 — 1Max Planck Institute for Polymer Research, 55128, Mainz, Germany — 2Leibniz Institute of Polymer Research, 01069, Dresden, Germany
The coalescence and interaction between two drops have been the subject of intensive studies in recent years , due to its wide range of application and the presence in the nature.
Here, we study the merging of partially miscible drop. We deposit drops of different liquids on a substrate. Under appropriate conditions, the merging process generates an instability which resembles the Rayleigh-Plateau instability. If the liquid with higher surface activity is deposited as a second droplet. Its vapor can diffuse through the air and induce a Marangoni flow inside the already deposited droplet. This induced flow can pull a thin liquid layer over the surface , which decays into drops by a Rayleigh-Plateau instability.
We present a detailed study of this instability analyzing the onset of the instability and its characteristic length scales. Finally, a model is presented to explain the Marangoni flow induced by the gas phase. This model is validated by particle tracking.
References  S. Karpitschka, C. Hanske, A. Fery, and H. Riegler, Langmuir, vol. 30, no. 23, pp. 6826*6830, 2014.