Method for research of pulsation dynamics of gas-vapor bubbles in cavitation process initiated by acoustic oscillations

The article describes the method for research of pulsation dynamics of gas-vapor bubbles in cavitation process initiated by acoustic oscillations. Acoustic cavitation, in contrast to hydrodynamic cavitation, is the periodic process, which repeats with driving force frequency (acoustic oscillations). This circumstance gives the possibility to carry out measurements of average size of bubbles inside the cavitation region in the fixed phase of acoustic oscillations. The essence of the proposed method is based on the fact that optical radiation formed by short (with duration on the order of 1/100 periods of acoustic oscillations) pulses are passed through the cavitation region. Time of pulse generation is synchronized with fixed phase of acoustic oscillations. The second optical radiation field formed as a result of scattering on the cavitation region is recorded by digital camera, shutter of which is opened for the period approximately equal to 100 periods of acoustic oscillations. As a result of the stroboscopic effect, the stationary image of scattering field is generated on the camera matrix. Then statistical processing of the obtained image is conducted. During this process average brightness of a scattering field in preset angular direction is determined. This parameter contains information about state of the cavitation region at given time.