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Updated: May 18, 2026
08:34
Visualization of High Speed Liquid Jet Impaction on a Moving Surface
Published on: April 17, 2015
von Kármán vortex street within an impacting drop.
Marie-Jean Thoraval1, Kohsei Takehara, Takeharu Goji Etoh
1Division of Physical Sciences and Engineering & Clean Combustion Research Center, King Abdullah University of Science and Technology (KAUST), Thuwal, 23955-6900, Saudi Arabia.
Physical Review Letters
|September 26, 2012
Summary
High-speed impact causes liquid jets to break into microdroplets. This study reveals how unstable liquid jets form vortex rings, leading to irregular splashing during drop impacts.
Area of Science:
- Fluid dynamics
- Microdroplet formation
- Splash dynamics
Background:
- Drop impact on liquid surfaces generates microdroplets.
- At high velocities, liquid jets are a primary source of these microdroplets.
- Understanding splash mechanisms is crucial for various applications.
Purpose of the Study:
- To investigate the mechanism of microdroplet generation from liquid jets during drop impact.
- To elucidate the transition from jetting to irregular splashing.
- To analyze the role of fluid instabilities in splash formation.
Main Methods:
- Ultrahigh-speed video imaging to capture dynamic events.
- High-resolution numerical simulations for detailed analysis.
- Investigating fluid instabilities at higher Reynolds numbers.
Main Results:
- Identified a thin liquid jet as the main source of microdroplets at high impact velocities.
- Observed the jet base becoming unstable at higher Reynolds numbers.
- Demonstrated the shedding of vortex rings from the free surface, forming an axisymmetric von Kármán vortex street.
- Showed that these vortex rings break the ejecta sheet as it forms, leading to irregular splashing.
Conclusions:
- The instability of liquid jets is the key mechanism driving irregular splashing.
- Vortex ring formation plays a critical role in the breakup of the ejecta sheet.
- This research provides insights into the fundamental physics of drop impact and microdroplet generation.
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