Minoru Kurosawa

Cavitation sensor with hydrothermally synthesized lead zirconate titanate polycrystalline film deposited on cylindrical titanium pipe: Estimation of acoustic cavitation field and basic characteristics of cavitation sensor

We have developed a small cavitation sensor by deposition of hydrothermally synthesized lead zirconate titanate polycrystalline film onto the outer surface of a hollow cylindrical titanium pipe. The spatial distribution of acoustic cavitation generated in the vessel of a 150 kHz sonoreactor was measured by using the broadband integrated voltage (BIV) calculated from the output signal of the cavitation sensor. A spatial distribution similar to the sonochemical luminescence pattern could be observed in the measured BIV results. We found that our fabricated cavitation sensor could measure the spatial distribution of acoustic cavitation in a high-intensity ultrasound field for a period exceeding 150 h without damage. We also measured the spatial distribution and directivity of the receiving sensitivity for characterization of the sensor. The measured results suggest that the BIV and cavitation signal included in the output signal of the cavitation sensor are a consequence of the acoustic cavitation generated ...

Development of tough anti cavitation hydrophone by deposition of hydrothermally synthesized lead zirconate titanate poly-crystalline film on reverse surface of titanium front layer

It is difficult to measure the high intensity ultrasound field with generation of acoustic cavitaion, since the electrode of hydrophone will be damaged by erosion and acoustic cavitation. Therefore, we developed the original miniature hydrophone by using hydrothermally synthesized lead zirconate titanate poly-crystalline film deposited on a reverse surface of a titanium film front layer as protection layer from damage by acoustic cavitation and erosion. Our hydrophone could be used to measure the high intensity ultrasound field with generation of acoustic cavitation such as focal area of 1.6 MHz HIFU treatment equipment and in a vessel of a 47 kHz ultrasound cleaner without any damage. However, we observed the output waveform of the hydrophone without nonlinear distortion in spite of measurement in high intensity ultrasound field like focal area of 1.6 MHz HIFU treatment equipment. We considered on the cause of above problem and its improving methods by computer simulation with MASONs equivalent circuit ...