Cavitation-induced shock wave behaviour in different liquids.
Mohammad Khavari1, Abhinav Priyadarshi2, Justin Morton2
1School of Computing and Engineering, College of Science and Engineering, University of Derby, Derby DE22 3AW, United Kingdom; Faculty of Technology, Design and Environment, Oxford Brookes University, Oxford OX33 1HX, United Kingdom.
Ultrasonics Sonochemistry
|February 21, 2023
Summary
Investigating shock waves from bubble collapse, this study found ethanol-water solutions generate significant pressure peaks, unlike pure ethanol or glycerol. These findings are crucial for understanding ultrasonic cavitation effects.
Area of Science:
- Acoustics
- Fluid Dynamics
- Materials Science
Background:
- Ultrasonic cavitation generates shock waves during bubble collapse.
- Previous work identified high-frequency pressure peaks in water due to shock waves.
Purpose of the Study:
- To investigate the influence of liquid physical properties on shock wave characteristics.
- To compare shock wave phenomena in water, ethanol, glycerol, and an ethanol-water solution.
Main Methods:
- Experiments involved ultrasonic excitation at 24 kHz.
- Pressure frequency spectra were analyzed from over 1.5 million cavitation bubble collapse events.
- Acoustic pressure maps were constructed for qualitative analysis.
Main Results:
- Prominent shock wave pressure peaks were detected in water and the ethanol-water solution, but not in ethanol or glycerol.
- The ethanol-water solution exhibited higher overall acoustic pressure amplitudes.
- Distinct shock wave features, including MHz frequency peaks and sub-harmonic generation, were observed.
Conclusions:
- Liquid properties significantly affect shock wave formation and characteristics during cavitation.
- Ethanol-water solutions show potential for enhanced pressure generation in ultrasonic applications.
- Mist-like patterns in ethanol-water solutions correlate with increased acoustic pressures.
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