激光空泡溃灭及其产生的声波  

Collapse of laser induced bubbles and generated sound pressure waves

作　　者：邓圆[1] 金韬[1] 池灏[1] 周金海[1] 

机构地区：[1]浙江大学信息与电子工程学系,杭州310027

出　　处：《强激光与粒子束》2013年第11期2793-2798,共6页High Power Laser and Particle Beams

基　　金：国家自然科学基金项目(61275027;2012BAH34B03);浙江大学海洋交叉项目(2012HY004A);国家重点基础研究发展计划项目(2012CB315703)

摘　　要：强激光脉冲在水中的自聚焦传输、成丝、击穿及击穿后产生的声波,近年来成为强激光脉冲传输应用研究领域的一个热点。强激光脉冲电离产生的空泡在溃灭过程中,对周围水体产生压缩,从而在水下产生声波。在现有理论基础上,考虑空泡含气量、水的粘滞系数和水的表面张力系数对空泡运动及其产生声波的影响。给出双空泡运动方程,分析空泡间距对空泡溃灭和其产生声压关系。根据实际情况,计算不同温度情况下单空泡和双空泡运动过程及其产生的声压,并进行相互比较。计算结果表明:水温越高,空泡运动时达到的最小半径越小,空泡振荡周期和溃灭时间延长,产生声压越高。随双空泡间距减小,空泡溃灭时达到的最小半径线性减小,而其产生的最大声压则单调增大。The self-focusing transmission,filamentation,breakdown of intense laser pulses in water,and sound pressure waves generated during breakdown become a hot topic of intense laser pulse application research.Ionization generated bubbles compress the surrounding water bodies,which produces sound pressure waves underwater.Based on the previous theory,a dynamic model is developed,in which the gas content,viscosity coefficient and the surface tension coefficient are considered.The collapse process of double bubbles is also modeled,which could be applied to calculate the bubble radius and generated sound pressure waves.These theories are amended by introducing varying factors of water characters at different temperatures.Calculation results show that the bubbles shrink more violently and generate higher sound pressure waves when water temperature is higher.For double bubbles,higher sound pressure waves will be generated when the two bubbles are closer.The minimum collapse radiuses are varying linearly along with the distances between bubbles,and the generated maximum sound pressures are monotonically increasing.

关 键 词：强激光脉冲 激光空泡 声压 单空泡 双空泡 

分 类 号：TN249[电子电信—物理电子学]