A Device for Cavitation Activity Measuremnts and Investigation
N.Dezhkunov (Belarusian State University of Informatics and Radioelrctronics, Minsk, Belarus)
A device for cavitation activity investigation and measurements, Cavitometer IC-3, is described in the presentation. The Cavitometer consists of an electronic block and a wide-band hydrophone protected against cavitation erosion. An operation principle is based on analysis and elaboration of cavitation noise spectra. This principle was backgrounded by investigation of cavitation noise spectra generated at different sonification conditions. Sonoluminescence intensity was measured simultaneously with noise spectra registration. It has been shown that at ultrasound intensities lower than the sonoluminescence (SL) threshold noise spectra contain a fundamental line, subharmonic and higher harmonics. The threshold of broadband component, so called .white noise., appearance coincides with the threshold of sonoluminescence. It has been shown that if cavitation conditions change in such a way that bubbles collapse rate is increased, both intensity of high frequency components (registered up to 10 MHz) and intensity of white noise are increased. The Cavitometer developed on the basis of the above results has following functions: measurement of transient bubbles activity, measurement of total bubbles activity, measurement of subharmonic intensity and measurement of fundamental frequency of the driving field. Also total calibrated hydrophone output may be registered with the help of the device.
Section : 11