Critical parameters for the partial coalescence of a droplet

Abstract

The partial coalescence of a droplet onto a planar liquid/liquid interface is investigated experimentally by tuning the viscosities of both liquids. The problem mainly depends on four dimensionless parameters: the Bond number (gravity vs. surface tension), the Ohnesorge numbers (viscosity in both fluids vs. surface tension), and the density relative difference. The ratio between the daughter droplet size and the mother droplet size is investigated as a function of these dimensionless numbers. Global quantities such as the available surface energy of the droplet has been measured during the coalescence. The capillary waves propagation and damping are studied in detail. The relation between these waves and the partial coalescence is discussed. Additional viscous mechanisms are proposed in order to explain the asymmetric role played by both viscosities.

16 pages, 14 figures, submitted to Physical Review E

References in corpus (1)

• Coalescence of Liquid Drops

Cited by in corpus (8)

• Coalescence of bubbles and drops in an outer fluid
• Impact of Droplets on Inclined Flowing Liquid Films
• Controlling the partial coalescence of a droplet on a vertically vibrated bath
• The asymmetric coalescence of two droplets with different surface tensions is caused by capillary waves
• Coalescence and spreading of drops on liquid pools
• Walking Droplets Through the Lens of Dynamical Systems
• Effect of velocity, fluid properties and drop shape on coalescence and neck oscillation
• Investigation of drop coalescence via transient shape evolution: A sequential event based approach