Translational motion of two interacting bubbles in a strong acoustic field
Translational motion of two interacting bubbles in a strong acoustic field
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DOI：
10.1103/physreve.64.026301
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发表时间：
2001-08-01
影响因子：
2.4
通讯作者：
Doinikov, AA
中科院分区：
文献类型：
--
作者：
Doinikov, AA
利用拉格朗日形式，导出了两个耦合球面气泡在气泡间距倒数方向上的径向和平动运动方程，最高可达三阶。为了考虑液体可压缩性的影响，采用Keller-Miksis方法对径向脉动方程进行了修正，并在平移方程中加入了Levich阻力形式的粘性力。然后将该模型用于两个小气泡的平移运动的数值研究，这些气泡在强声场中被驱动到远低于共振的位置，压力幅度超过1bar。研究发现，如果作用力足够强，气泡就会形成一对具有稳定间距的束缚对，而不是像经典的比耶克内斯理论预测的那样，发生碰撞和合并。此外，粘性作用力会导致系统中的偏斜，从而导致气泡对的自推进。后者作为一个单位沿中心线沿由初始气泡半径之比确定的方向行进。所得结果对于理解和模拟声空化流光等强场中的集体气泡现象具有直接的意义。
Using the Lagrangian formalism, equations of radial and translational motions of two coupled spherical gas bubbles have been derived up to terms of third order in the inverse distance between the bubbles. The equations of radial pulsations were then modified, for the purpose of allowing for effects of liquid compressibility, using Keller-Miksis' approach, and the equations of translation were added by viscous forces in the form of the Levich drag. This model was then used in a numerical investigation of the translational motion of two small, driven well below resonance, bubbles in strong acoustic fields with pressure amplitudes exceeding 1 bar. It has been found that, if the forcing is strong enough, the bubbles form a bound pair with a steady spacing rather than collide and coalesce, as classical Bjerknes theory predicts. Moreover, the viscous forces cause skewness in the system, which results in self-propulsion of the bubble pair. The latter travels as a unit along the center line in a direction that is determined by the ratio of the initial bubble radii. The results obtained are of immediate interest for understanding and modeling collective bubble phenomena in strong fields, such as acoustic cavitation streamers.