Study of measurement of the amount of generated acoustic cavitation: Relationships among broadband integrated voltage, dissolved oxygen, and sonochemical luminescence

We have been investigated a technique for quantitatively measuring generated acoustic cavitation. Recently, several applications that use cavitation have been developed in the fields of medicine, cleaning, and sonochemistry. However, cavitation can also cause undesired damage, for example, to normal cells in the human body and cleaning objectives. Therefore, the amount of generated cavitation must be adequately controlled, toward that end, a suitable measurement technique is necessary. Conventional methods for investigation of cavitation do not measure the signal generated by the cavitation. Consequently, a more precise technique is needed to ensure the safety and effectiveness of cavitation applications. Therefore, we used the broadband integrated voltage (BIV) calculated from the high frequency components of the broadband noise produced by cavitation bubbles. BIV is less susceptible to the influence of nonlinear propagation of ultrasound. In this study, the characteristics of BIV were investigated by dissolved oxygen level which was cavitation generation condition and sonochemical luminescence which was sonochemical reaction. Also, the one dimensional distribution of cavitation generation was measured in terms of BIV. As a result, BIV was found to depend on the dissolved oxygen level in distilled water. A correlation was also found between BIV and sonochemical luminescence. These results show that BIV has the potential to be used as an index of the amount of generated cavitation. In addition, in comparison with sound pressure measured with a hydrophone, BIV had a potential that the spatial distribution of cavitation generation could be measured accurately than sound pressure.