ACOUSTIC MICROCAVITATION - ITS ACTIVE AND PASSIVE ACOUSTIC DETECTION
ACOUSTIC MICROCAVITATION - ITS ACTIVE AND PASSIVE ACOUSTIC DETECTION
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DOI：
10.1121/1.401891
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发表时间：
1991-09-01
影响因子：
2.4
通讯作者：
APFEL, RE
中科院分区：
文献类型：
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作者：
MADANSHETTY, SI;ROY, RA;APFEL, RE
在这项工作中，在水中的声微空化研究主要是在0.75 MHz和1%的占空比。 为了检测空化，两种类型的声学检测器是未聚焦的、未调谐的1 MHz接收换能器，其用作被动检测器。 另一个是聚焦30 MHz换能器，用于脉冲回波模式，称为主动探测器。 空化本身是由脉冲模式驱动的聚焦PZT-8晶体引起的。 有源检测器相对于空化换能器共焦地布置。 询问脉冲和空化脉冲两者同时到达公共焦点，该公共焦点是空化区域。 在试验室充满清洁水的情况下，没有观察到气穴现象，甚至当气穴传感器被驱动以给出其22巴峰值负输出时也是如此。 然而，当聚苯乙烯微粒被添加到宿主水中时，观察到空化。 我们认为，这些光滑的，球形的，单分散的微粒如何引起空化描述与一些估计。 已经尝试理解“流”的存在是否影响阈值，并且已经发现，活动检测器场影响空化过程。
In this work acoustic microcavitation in water is studied primarily at 0.75 MHz and 1% duty cycle. To detect cavitation, two kinds of acoustic detectors are unfocused, untuned 1-MHz receiver transducer that serves as a passive detector. The other one is a focused 30-MHz transducer that is used in pulse-echo mode and is called the active detector. Cavitation itself is brought about by a focused PZT-8 crystal driven in pulse mode. The active detector is arranged confocally with respect to the cavitation transducer. Both the interrogating pulse and the cavitation pulse arrive simultaneously at the common focus, which is the region of cavitation. With the test chamber filled with clean water, no cavitation is observed, even when the cavitation transducer is driven to give its peak output of 22 bar peak negative. Cavitation is, however, observed when polystyrene microparticles are added to the host water. Our view of how these smooth, spherical, monodispersed microparticles give rise to cavitation is described with some estimates. An attempt has been made to understand whether the presence of "streaming" affects the thresholds, and it has been found that the active detector field affects the cavitation process.