Related Experiment Video
Updated: Jun 24, 2025
08:49
Impacts of Free-falling Spheres on a Deep Liquid Pool with Altered Fluid and Impactor Surface Conditions
Published on: February 17, 2019
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Drop impact onto immiscible liquid films floating on pools
Ben D Fudge1,2, Radu Cimpeanu2,3, Alfonso A Castrejón-Pita4
1Department of Engineering Science, University of Oxford, Oxford, OX1 3PJ, UK.
Scientific Reports
|June 13, 2024
Summary
This study examines droplet impact on a liquid pool coated with a second fluid layer. We quantified how film thickness affects droplet penetration, revealing transitional behaviors and new insights into multi-fluid dynamics.
Area of Science:
- Fluid dynamics
- Multiphase flow
- Interface phenomena
Background:
- Droplet impact dynamics onto liquid pools are well-understood for single-fluid systems.
- Previous research quantified interfacial velocities for same-fluid and different-fluid impacts.
Purpose of the Study:
- To investigate droplet impact on a liquid pool coated by a fluid layer of varying thickness.
- To measure the effect of film thickness on droplet penetration velocity.
- To compare experimental and computational results with theoretical predictions.
Main Methods:
- Experimental investigation of droplet impact dynamics.
- Computational fluid dynamics (CFD) simulations.
- Analysis of interfacial velocity and flow quantities.
Main Results:
- Quantified the effect of film thickness on the upper droplet-film interface penetration velocity.
- Observed robust transitional behavior between zero and infinite film thickness limits.
- Demonstrated that films up to one impacting drop diameter can significantly alter post-impact dynamics.
Conclusions:
- Provided new quantitative insights into nonlinear behavior in multi-fluid systems.
- Delineated the influence of finite film thicknesses in droplet-pool impact scenarios.
- Identified that increased liquid film viscosity leads to lower velocities and larger film thicknesses at longer timescales.
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