Cavitation activation by dual-frequency ultrasound and shock waves
Adam Brotchie, Robert Mettin, Franz Grieser, Muthupandian Ashokkumar
PHYSICAL CHEMISTRY CHEMICAL PHYSICS | ROYAL SOC CHEMISTRY | Published : 2009
High-speed photographic observations of cavitation occurring under a low-frequency (21 kHz) sonotrode tip in the presence of an additional, high-frequency (355 kHz) ultrasound source have been made in water and in dilute aqueous solute solutions. Acoustic emission spectra were measured to support the visual observations. It was seen that a nucleating effect of the high-frequency action on cavitation at the low-frequency sonotrode was highly power dependent, with cavitation being homogenous at low acoustic power and highly localised at high acoustic power. The presence of solutes was found to significantly affect the cavitation structures and the bubble fragmentation process. Both the fundame..View full abstract
The authors thank the help provided by Mohsen Alizadeh, Till Nowak and Fabian Reuter. A. B. gratefully acknowledges financial support received from an Australian Postgraduate Award (APA), Melbourne University Postgraduate Overseas Research Experience Scholarship ( PORES), Tom Healy Award and the Particulate Fluids Processing Centre (PFPC).