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Self-Similar Liquid Lens Coalescence
Michiel A Hack1, Walter Tewes1, Qingguang Xie2
1Physics of Fluids Group, Faculty of Science and Technology, University of Twente, P.O. Box 217, 7500 AE Enschede, The Netherlands.
Physical Review Letters
|May 30, 2020
Summary
Liquid drops merge on prewetted surfaces, forming a bridge that grows vertically. This study reveals the dynamics of this liquid lens coalescence, offering insights into fluid dynamics and surface interactions.
Area of Science:
- Fluid dynamics
- Surface science
- Physics of liquids
Background:
- Drop coalescence is fundamental to many applications.
- Coalescence on prewetted substrates is less understood.
- Liquid lenses merge upon contact, forming a larger drop.
Purpose of the Study:
- To experimentally and theoretically investigate drop coalescence on thick, low-viscosity liquid layers.
- To reveal the dynamics of liquid lens merging.
- To develop a predictive model for coalescence.
Main Methods:
- Experimental observation of drop coalescence.
- Theoretical analysis using slender flow theory.
- Derivation of similarity solutions for viscous and inertial regimes.
Main Results:
- Liquid lenses merge via self-similar vertical bridge growth.
- The derived similarity solutions accurately predict experimental results without adjustable parameters.
- A unified curve describes the crossover between viscous and inertial coalescence regimes.
Conclusions:
- The study provides a comprehensive understanding of liquid lens coalescence dynamics.
- The findings are applicable to various scientific and industrial processes involving liquid merging.
- Accurate models for drop coalescence on prewetted surfaces have been established.
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