在声学静止波中对稳定的悬浮位置的粒子大小效应
Wolfgang Rueckner1, Joseph Peidle1, Allen Crockett1
1Harvard University Science Center, Harvard University, 1 Oxford Street, Cambridge, Massachusetts 02138, USA.
The Journal of the Acoustical Society of America
|August 31, 2023
概括
聚烯泡球体的大小会影响它们在超声波声学静止波中悬浮的位置. 较小的球体聚集在压力节点上,而较大的球体则在压力反节点上定位.
科学领域:
- 声学 声学 在声学方面
- 流体动力学 流体动力学
- 材料科学 材料科学 材料科学
背景情况:
- 施莱伦成像可视化压力分布,有助于理解声学现象.
- 之前的研究探讨了声场中的粒子行为,但粒子大小效应需要进一步澄清.
研究的目的:
- 为了研究粒子大小对固体弹性聚烯泡球体悬浮的影响.
- 为了将球体大小与它们在超声波声学静止波中的位置 (节点与反节点) 相关联.
主要方法:
- 使用施莱伦成像来获得压力分布的二维表示.
- 对超声波静止波进行压力测量.
- 观察并分析了不同尺寸的聚烯泡球体的悬浮行为.
主要成果:
- 在超声波声学静止波悬浮中证明了粒子大小效应.
- 在压力节点上悬浮的直径<0.58λ (波长) 的球体.
- 具有直径>0.66λ的球体在压力反点上悬浮,中心在压力反点上.
结论:
- 球体大小是决定在超声波声学静止波中悬浮位置的关键因素.
- 这些发现与之前关于粒子悬浮动力学的实验和理论研究保持一致并扩展.
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