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Updated: Jul 14, 2026

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Fast Imaging Technique to Study Drop Impact Dynamics of Non-Newtonian Fluids
Published on: March 5, 2014
Understanding cavity dynamics near deformable oil drop via numerical simulations.
Deepak K Pandey1, Rupak Kumar1, Vivek V Ranade1
1Multiphase Reactors and Intensification Group, Bernal Institute, University of Limerick, Limerick V94T9PX, Ireland.
Ultrasonics Sonochemistry
|March 28, 2025
Summary
Cavitation
Area of Science:
- Fluid dynamics
- Chemical engineering
- Materials science
Background:
- Cavitation is a key process for liquid-liquid emulsification.
- Cavity collapse generates microscale jets crucial for emulsification.
- Understanding cavity-droplet interactions is vital for optimizing emulsification.
Purpose of the Study:
- To numerically investigate single cavity-droplet interactions in a hydrodynamic cavitation device.
- To analyze the effects of droplet-cavity size ratio (β) and stand-off parameter (γ) on dynamics.
- To evaluate the influence of these parameters on cavity jet velocity and energy dissipation.
Main Methods:
- Direct numerical simulation using the multi-fluid, Volume of Fluid (VOF) method.
- Simulated various scenarios of cavity-droplet interactions.
- Evaluated cavity jet velocity (Umax) and energy dissipation rate (ε).
Main Results:
- Cavity jet velocity initially increases then decreases with the stand-off parameter.
- Cavity jet velocity increases and plateaus with the size ratio.
- Maximum jet velocity observed at specific β and γ values (e.g., β=2.5, γ=0.7 and β=5, γ=1.2).
- Energy dissipation rate is consistently around 10^8 m²/s³.
Conclusions:
- The study enhances fundamental understanding of cavity-droplet interactions in emulsification.
- Results provide a basis for developing cavitation-induced droplet breakage models.
- Findings enable improved emulsification applications in chemical industries.
Keywords:
Cavity jet velocityCavity-droplet interactionCavity/ droplet sizeEnergy dissipation rateVOFMore Related Videos
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