在可听到的声音驱动的气泡中进行质量和热量转移
Davide Masiello1, Ignacio Tudela1, Stephen J Shaw2
1School of Engineering, The University of Edinburgh, Sanderson building, Robert Stevenson Road, Edinburgh EH9 3FB, United Kingdom.
Ultrasonics sonochemistry
|October 11, 2024
概括
现有的泡动力学模型准确地预测了超声波频率的行为,但在可听的声音水平上失败了. 这项研究引入了一种混合模型,突出了低频率泡大小,温度和压力预测的显著偏差.
科学领域:
- 声学和流体动力学 声学和流体动力学
- 物理化学 物理化学
- 计算建模 计算建模
背景情况:
- 声光发射和声化学研究主要使用20kHz以上的频率.
- 声学驱动的气泡动力学的数学模型在可听的频率范围 (低于20kHz) 很少.
研究的目的:
- 开发和验证一种混合建模方法,用于通过可听声音驱动的惯性崩的气泡.
- 为了评估低声频率下降顺序模型的准确性,与更严格的偏向-扩散模型相比.
主要方法:
- 开发了一种新的混合模型,结合了向-扩散和边界层方法.
- 预测了气泡中的相变,质量和热传递.
- 对超高速视频中的 17.8 kHz 气泡动态的实验数据进行了验证.
主要成果:
- 边界层模型在可听的频率 (例如17.8 kHz) 上显示了与向-扩散模型的显著偏差.
- 减少顺序模型过度预测气泡大小和被困蒸汽,同时低频率预测温度和压力.
- 偏差源于不准确的边界层厚度估计,原因是扩散和泡壁运动之间的时间尺度竞争.
结论:
- 现有的针对超声波频率开发的缩小序列模型不适合于可听范围.
- 进一步研究可听频谱内的气泡动力学建模是必不可少的.
- 开发的混合模型为研究可听声音诱导的泡行为提供了更准确的方法.
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