非线性超声束的冲击波形成研究  

Study on the shock formation in a nonlinear ultrasound beam

作　　者：陶超[1] 马健[1] 朱哲民[1] 杜功焕[1] 平自红[2] 

机构地区：[1]南京大学声学研究所近代声学国家重点实验室,南京210093 [2]杭州应用声学研究所,杭州富阳311400

出　　处：《声学学报》2004年第2期115-121,共7页Acta Acustica

基　　金：国家自然科学基金(19834040和10074035)

摘　　要：通过用频域方法数值求解KZK方程;以活塞声场为例,研究了非线性超声束的冲击波形成规律。结果表明:除了非线性强度、吸收外,衍射是另一个影响非线性超声束冲击波形成的重要因素。文章发现在不同的衍射条件下的活塞声场的冲击波形成距离有很大差异。最后,还比较了不同参数下冲击波形成时的声压波形和冲击波形成的空间分布。The shock formation in a nonlinear ultrasound beam by solving KZK equation using frequency-domain numerical method is investigated. The results reveal that besides the nonlinearity and absorption, the diffraction is another important factor that affects the shock formation of an ultrasound beam. It also reveals that the shock formation distances of piston field are much different under different diffraction conditions. At last, the waveform of sound pressure at the formation of shock and the spatial distribution of shock formation are also presented and discussed.

关 键 词：非线性超声束 冲击波 KZK方程 活塞声场 声压波形 声波衍射 

分 类 号：O426[理学—声学]