脉动气泡在黏性介质中的声发射  

Acoustic emission of pulsating bubbles in viscous media

作　　者：申潇卓 吴鹏飞[1,2] 林伟军 Shen Xiao-Zhuo;Wu Peng-Fei;Lin Wei-Jun(State Key Laboratory of Acoustics,Institute of Acoustics,Chinese Academy of Sciences,Beijing 100190,China;University of Chinese Academy of Sciences,Beijing 100049,China)

机构地区：[1]中国科学院声学研究所,声场声信息国家重点实验室,北京100190 [2]中国科学院大学,北京100049

出　　处：《物理学报》2024年第17期216-224,共9页Acta Physica Sinica

基　　金：中国科学院基础前沿研究计划从0到1原始创新项目(批准号:ZDBS-LY-SLH037);中国科协青年人才托举工程(批准号:2022-2024QNRC001);中国科学院青年创新促进会(批准号:2023031)资助的课题.

摘　　要：在气泡辐射声问题中一直被使用的气泡声发射公式并未考虑介质的黏性在声波传播过程中产生的影响.本文结合气泡的边界条件,对黏性介质中的声波方程进行求解,给出黏性介质中经过修正的气泡的声发射公式,进行气泡动力学方程求解和有限元仿真等数值计算后发现,在考虑介质的黏性时,本文提出的黏性介质中气泡声发射公式所计算出的声压小于经典气泡声发射公式计算出的声压,并且随着介质黏度、超声频率以及传播距离的增加,二者之间的误差逐渐增大.The classical single bubble’s acoustic emission equation has been used to describe the sound filed radiated by bubble for a long time.Because this formula does not consider the influence of the medium viscosity in the process of sound wave propagation,it is more reasonable to modify it in some special cases.Based on the boundary condition of the bubbles,i.e.the vibration velocity of the bubble wall is equal to the particle vibration velocity of the external medium at the bubble boundary,the acoustic wave equation in spherical coordinate system in viscous medium is solved,and the modified acoustic emission formula of the bubble in the viscous medium is given.The bubble radius R(t)is obtained numerically from the bubble dynamics equation by using the fourthfifth order Runge-Kutta method.Then the bubble's radiation sound field is obtained by using the direct substitution method and the finite element(The pressure acoustics module;two-dimensional(2D)axisymmetric geometric model)method,respectively.The modified expression ppresent given in this work is more accurate to describe the bubble’s radiation than the classical expression p_(classical) in the cases of high-viscosity,high-frequency and long-distance.In these cases,continuing to measure the acoustic emission of bubbles by using the classical expression may have an influence on the characteristics of cavitation,such as the inaccurate descriptions of parameters such as cavitation intensity and cavitation threshold.

关 键 词：气泡声发射 黏滞声波方程 气泡动力学 有限元仿真 

分 类 号：O35[理学—流体力学]