多重散射理论用于在大气流中建模声波爆炸
1National Aeronautics and Space Administration (NASA) Langley Research Center, 2 North Dryden Street (Mail Stop 463), Hampton, Virginia 23681, USA.
The Journal of the Acoustical Society of America
|November 14, 2023
概括
这项研究引入了一种新的声波爆发传播模型,其中包括流散射效应. 研究结果表明,流散射加厚冲击,并减少声波爆发能量.
科学领域:
- 声学 声学 在声学方面
- 流体动力学 流体动力学
- 波浪传播 波浪传播
背景情况:
- 声波爆炸通常使用汉堡方程建模,不考虑流散射.
- 流散射是一种普遍存在的效应,可以在测量到的声波爆炸中观察到.
研究的目的:
- 用多重散射理论来制定流对声波爆发的平均散射效应.
- 扩展汉堡方程,以纳入这些散射效应.
主要方法:
- 使用多重散射理论和整体平均值来制定平均散射效应.
- 导出一个声波-流相互作用能量和一个复杂值的散射波数.
- 用线性项来扩展伯格斯方程的分散效应.
- 对N波和低波形的数值模拟.
主要成果:
- 波数的散射会导致平均波形的分散和减弱.
- 模拟显示了冲击加厚,峰值振幅降低,声波爆发中的能量含量降低.
- 与N波相比,低波波的能量减少不那么严重,并且取决于流特性.
结论:
- 扩展的伯格斯方程准确地模拟了流对声波爆炸的平均散射效应.
- 流散射显著改变了声波爆发特征,包括波形形状和能量.
- 这项研究为在动荡环境中更准确地预测声波爆发提供了一个框架.
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