A method for estimating time-dependent acoustic cross-sections of bubbles and bubble clouds prior to the steady state
A method for estimating time-dependent acoustic cross-sections of bubbles and bubble clouds prior to the steady state
复制标题
一种估计稳态之前气泡和气泡云的时间相关声学横截面的方法
DOI：
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复制
发表时间：
2000
影响因子：
2.4
通讯作者：
Leighton
中科院分区：
文献类型：
--
作者：
Clarke;Leighton
液体中稳态脉动气泡声截面的模型已经存在了一段时间。本文提出了一种理论方案，用于估计单个气泡和气泡云的横截面，从开始的声波向前。在此期间，瞬态的存在可以显著改变稳态值的横截面。该模型结合了Herring-Keller模型的数值解与适当的阻尼值来计算作为时间的函数的气泡的消光截面，以响应于连续的谐波声场（它也示出了该模型如何可以适应于估计随时间变化的散射截面）。然后，该模型被扩展到确定灭绝截面面积的多个气泡的不同人口分布假设没有气泡-气泡相互作用。结果表明，达到稳态所需的时间取决于气泡与共振的接近程度和驱动压力的幅值。在总体响应中，达到稳态的时间随着驱动压力幅值的增大而减小;并且随着半径远大于共振的气泡的数量与共振气泡的数量的比率的增大而减小。这些研究结果的影响，使用声脉冲进行了探讨。
Models for the acoustic cross-sections of gas bubbles undergoing steady-state pulsation in liquid have existed for some time. This article presents a theoretical scheme for estimating the cross-sections of single bubbles, and bubble clouds, from the start of insonation onward. In this period the presence of transients can significantly alter the cross-section from the steady-state value. The model combines numerical solutions of the Herring-Keller model with appropriate damping values to calculate the extinction cross-section of a bubble as a function of time in response to a continuous harmonic sound field (it is also shown how the model can be adapted to estimate the time-dependent scatter cross-section). The model is then extended to determine the extinction cross-section area of multiple bubbles of varying population distributions assuming no bubble-bubble interactions. The results have shown that the time taken to reach steady state is dependent on the closeness of the bubble to resonance, and on the driving pressure amplitude. In the response of the population as a whole, the time to reach steady state tends to decrease with increasing values of the driving pressure amplitude; and with the increasing values of the ratio of the numbers of bubbles having radii much larger than resonance to the number of resonant bubbles. The implications of these findings for the use of acoustic pulses are explored.