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Updated: Jun 25, 2026
08:34
Visualization of High Speed Liquid Jet Impaction on a Moving Surface
Published on: April 17, 2015
High-speed jet formation after solid object impact
Stephan Gekle1, José Manuel Gordillo, Devaraj van der Meer
1Department of Applied Physics, University of Twente, P.O. Box 217, 7500 AE Enschede, The Netherlands.
Physical Review Letters
|March 5, 2009
Summary
When a disc impacts water, a jet forms from the collapsing cavity. Colliding cavity walls drive local flow, feeding the jet, not the hyperbolic pattern.
Area of Science:
- Fluid dynamics
- Impact physics
- Acoustics
Background:
- Circular disc impact on water generates craters and jets.
- Cavity pinch-off creates stagnation points and hyperbolic flow patterns.
- The mechanism feeding these jets has been debated.
Purpose of the Study:
- To investigate the fluid dynamics behind jet formation after cavity pinch-off.
- To identify the primary mechanism responsible for jet propulsion.
- To develop a quantitative model for jet formation.
Main Methods:
- High-speed imaging techniques to capture transient phenomena.
- Numerical simulations to analyze fluid flow patterns.
- Comparison of experimental data with theoretical models.
Main Results:
- Jetting is primarily fed by local flow near the jet base, driven by colliding cavity walls.
- The hyperbolic flow pattern is not the main source for jet propulsion.
- A new quantitative model for jet formation was developed beyond cavity pinch-off.
Conclusions:
- The colliding cavity walls are the dominant factor in jet formation.
- The developed model accurately predicts jet behavior, aligning with experimental and simulation data.
- This research clarifies the physics of jetting in impact events.
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