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Updated: Jan 5, 2026
07:08
Film Control to Study Contributions of Waves to Droplet Impact Dynamics on Thin Flowing Liquid Films
Published on: August 18, 2018
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Initial coalescence of a drop at a planar liquid surface
Qindan Zhang1,2, Xiaofeng Jiang1, David Brunello1
1Laboratory of Reactions and Process Engineering, CNRS, University of Lorraine, 1, rue Grandville, BP 20451, 54001 Nancy Cedex, France.
Physical Review. E
|October 24, 2019
Summary
This study investigates liquid drop coalescence using advanced imaging and electrical methods. Findings reveal distinct flow regimes and the dominant role of inertia in highly viscous liquids.
Area of Science:
- Fluid Dynamics
- Rheology
- Surface Science
Background:
- Understanding liquid drop coalescence is crucial for various industrial processes.
- Previous studies primarily focused on Newtonian fluids and drop-drop configurations.
Purpose of the Study:
- To investigate the initial coalescence of a pendant drop onto a bulk liquid.
- To extend the understanding of coalescence dynamics to highly viscous non-Newtonian liquids.
- To elucidate the energy transformation and dominant forces during coalescence.
Main Methods:
- Utilized an ultrahigh-speed DC electrical device for precise measurements.
- Employed a high-speed camera for visual observation.
- Applied micro-Particle Image Velocimetry (micro-PIV) to analyze flow fields.
Main Results:
- Coalescence width variation with time confirmed distinct regimes (linear, square root, logarithmic).
- Identified specific regimes for inertially limited viscous and inertial phases.
- Observed the transformation of surface energy into kinetic energy during coalescence.
Conclusions:
- Inertia plays a dominant role over viscous forces in highly viscous non-Newtonian liquid coalescence.
- The study provides new insights into the physics of drop coalescence in complex fluids.
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