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在评述当前声空化研究领域的最新进展基础上,报道在声空化泡动力学理论和实验方面的研究结果.首先,考虑了实际非球对称声场驱动下的空化泡运动,提出了一个非球形气泡动力学模型,数值计算给出一种新的稳定的非球形振荡解.然后,设计了双路Mie散射系统,对空化泡运动的球对称性进行了实验检测,发现在低声压驱动的大气泡中存在明显的不同方向的非同步振荡.作为一个推论,得到了空化泡非球形振荡的证据.并且完成了非球形振荡和驱动参数、液体参数的相关性测量,具体参数包括驱动超声的幅度、频率,液体的表面张力系数、黏度、含气量等.最后,介绍了数字移相频闪照明拍摄技术,实现对稳态声空化泡的直接拍摄测量,时间分辨率提升到20ns,相比已有的200ns的时间分辨率,提高了一个量级.
Based on the review of the recent progress in the field of acoustic cavitation research, the results of the research on the theory and experimental aspects of the acoustic cavitation bubble dynamics are reported.Firstly, considering the cavitation bubble motion driven by the actual aspheric sound field, a Non-spherical bubble dynamics model, a new stable non-spherical oscillatory solution is given by numerical calculation.Then, a two-way Mie scattering system is designed to test the spherical symmetry of cavitation bubbles experimentally. There are obvious non-synchronous oscillations of different directions in the large pressure-driven bubble. As a corollary, we obtained the evidence of non-spherical oscillation of cavitation bubble and completed the measurement of the correlation between non-spherical oscillation and driving parameters and liquid parameters. The specific parameters Including the amplitude and frequency of driving ultrasound, the surface tension coefficient, viscosity and gas content of liquid.Finally, the digital phase-shift strobe illumination technology is introduced to realize the direct shooting measurement of steady state acoustic cavitation bubble and the improvement of time resolution By 20ns, it is an order of magnitude higher than the 200ns’ existing time resolution.