title: Dynamics of drops – Formation, growth, oscillation, detachment, and coalescence.
abstract: Single drops or bubbles are frequently used for the characterization of liquid-fluid interfaces. Their advantage is the small volume and the various protocols of their formation. Thus, several important methods are based on single drops and bubbles, such as capillary pressure and profile analysis tensiometry. However, these methods are often applied under dynamic conditions, although their principles are defined under equilibrium conditions. Thus, specific attention has to be paid when these methods are used beyond certain limits. In many cases, computational fluid dynamics (CFD) simulations have allowed researchers, to extend these limits and to gain important information on the interfacial dynamics. Examples discussed here are the capillary pressure tensiometry used for short time and profile analysis tensiometry for long time dynamic interfacial tension measurements, the oscillating drop methods for measuring dilational visco-elasticity. For measuring the coalescence of two drops the liquid dynamics of the subsequently formed liquid bridges have to be considered. In this paper, a thorough review of important experimental and computational findings, related to the dynamics of drops, including its formation, growth, oscillation, detachment, and coalescence is presented. Emphasis is however on some selected important developments. In addition, the paper tries to predict the main directions of advancement in interfacial research for the near future.
authors.affiliation: Max Planck Institute of Colloids and Interfaces, Potsdam/Golm, Germany. Electronic address: mohsen.karbaschi@mpikg.mpg.de.
authors.forename: M
authors.initials: M
authors.lastname: Karbaschi
authors.affiliation: Max Planck Institute of Colloids and Interfaces, Potsdam/Golm, Germany; Sharif University of Technology, Tehran, Iran.
authors.forename: M
authors.initials: M
authors.lastname: Taeibi Rahni
authors.affiliation: Max Planck Institute of Colloids and Interfaces, Potsdam/Golm, Germany; University of Tehran, Tehran, Iran.
authors.forename: A
authors.initials: A
authors.lastname: Javadi
authors.affiliation: Cronan Creative Solutions LLC, WI, USA.
authors.forename: C L
authors.initials: CL
authors.lastname: Cronan
authors.affiliation: Gamma-Service, Berlin, Germany.
authors.forename: K H
authors.initials: KH
authors.lastname: Schano
authors.affiliation: Max Planck Institute of Colloids and Interfaces, Potsdam/Golm, Germany.
authors.forename: S
authors.initials: S
authors.lastname: Faraji
authors.affiliation: Max Planck Institute of Colloids and Interfaces, Potsdam/Golm, Germany.
authors.forename: J Y
authors.initials: JY
authors.lastname: Won
authors.affiliation: Lafayette College, Easton, PA 18042, USA.
authors.forename: J K
authors.initials: JK
authors.lastname: Ferri
authors.affiliation: Max Planck Institute of Colloids and Interfaces, Potsdam/Golm, Germany.
authors.forename: J
authors.initials: J
authors.lastname: Krägel
authors.affiliation: Max Planck Institute of Colloids and Interfaces, Potsdam/Golm, Germany.
authors.forename: R
authors.initials: R
authors.lastname: Miller
keywords: Computational fluid dynamics simulation; Drop dynamics; Drop growing and oscillation; Drop-based experimental techniques; Drops coalescence and drop–drop interactions; Dynamics of liquid bridges