Contribution
Acoustic Cavitation Effects at Reduced Static Pressure
* Presenting author
Abstract:
Acoustic cavitation under reduction of ambient pressure is attracting certain interest in the context of ultrasonic cleaning, chemical processing and sonochemistry. Low air pressure is also partly used in hydrodynamic cavitation tunnel experiments. However, the literature on bubble dynamics and cavitation effects under low ambient pressure is sparse, which is the motivation for our studies. We employ a 20 kHz sonotrode setup in a vacuum box to investigate in water the general cavitation bubble fields and structures, bubble sizes and dynamics, erosion and cleaning, as well as cavitation interaction with small object structures. An important observation is that the dissolved gas content in the liquid plays a major role in such acoustic setups, since degassing under partial vacuum is strongly amplified by ultrasound, and degassing bubbles interfere with inertial cavitation.